Knee

Abstract:

PURPOSE:

To compare the displacement, stiffness, and ultimate failure load of a fixed-loopcortical suspensory device with 2 adjustable-loop devices when positioned on metaphysealbone.

METHODS:

Thirty devices (10 of each device) were positioned on the metaphyseal cortex of 30 porcine femora simulating anatomic anterior cruciate ligament femoral tunnel placement. Bovine tendons were used for soft tissue grafts, and the constructs were then cycled 1,000 times and pulled to failure, measuring displacement, stiffness, and failure load.

RESULTS:

Initial displacement, cyclic displacement, and total displacement were 2.98 mm, 2.09 mm, and 5.08 mm for the Endobutton CL (ECL), 2.82 mm, 2.27 mm, and 5.09 mm for the Tightrope (TRT), and 4.25 mm, 3.19 mm, and 7.44 mm for the adjustable-loop ToggleLoc Inline with Ziploop (TLZ), respectively. There was no difference between the ECL and the TRT on any measured outcome. Differences between the TLZ and ECL were statistically significant (initial displacement P = .024, cyclic displacement P < .001, and total displacement P < .001), as were those between the TLZ and TRT (initial displacement P = .010, cyclic displacement P = .001, and total displacement P < .001). Failure loads were 804 N, 801 N, and 682 N for the TRT, ECL, and TLZ, respectively, with no statistically significant difference.

CONCLUSIONS:

When positioned on the metaphyseal cortex, there was no difference in the biomechanical performance of the fixed-loop ECL and adjustable-loop TRT, and no lengthening of the TRTs was observed during cycling. However, the TLZ showed statistically significantly lower stiffness and more displacement during cycling with lengthening of the adjustable loop, the clinical significance of which is unknown.

CLINICAL RELEVANCE:

When used for femoral-sided soft tissue graft fixation in an anatomically placed femoral tunnel, the adjustable-loop TRT was biomechanically equivalent to the fixed-loop ECL. However, the adjustable-loop TLZ showed displacement during biomechanical testing that could potentially contribute to clinical failure after anterior cruciateligament reconstruction. However, the clinical significance was not directly tested

Abstract:

BACKGROUND:

Multiple techniques for patellar fixation with classic solid suture anchors(SAs) in medial patellofemoral ligament (MPFL) reconstruction have been described. Fixation of the graft to the patella with all-soft suture anchors (ASAs) has not been studied. Purpose/Hypothesis: To evaluate the biomechanical performance of 2 different MPFL patellar fixation techniques: ASA fixation and SA fixation. We hypothesized that the ASA group would show no statistical difference in the ultimate failure load and stiffness compared with the SA group.

STUDY DESIGN:

Controlled laboratory study.

METHODS:

Reconstruction of the MPFL with gracilis autografts was performed in 16 fresh-frozen cadaveric knees (mean age, 52.6 ± 9.0 years). The specimens were randomly assigned to 2 groups of 8 specimens each based on the method used to fix the graft to the medial patella: ASA or SA fixation. Patellar fixation with ASAs was completed with 2 parallel 1.8-mm anchors (Q-Fix, Smith & Nephew). Fixation with SAs was completed with 2 parallel 2.9-mm anchors (Osteoraptor, Smith & Nephew). The reconstructions were cyclically loaded for 10 cycles to 25 N and then loaded in tension at 6 mm/s until failure. Ultimate failure load (N), displacement (mm), stiffness (N/mm), and mode of failure were recorded for each specimen.

RESULTS:

Load to failure testing showed an ultimate failure load of 228.5 ± 53.1 N in the ASA group. In the SA group, the ultimate failure load was 156.2 ± 84.9 N. The difference between the 2 groups was not statistically significant ( P = .064). Stiffness values between the ASA and SA groups were not significantly different (21.3 ± 4.1 N/mm vs 20.9 ± 9.3 N/mm, respectively, P = .905). The most common mode of failure in both groups was anchor pullout (8 of 8 in the ASA group; 6 of 8 in the SA group).

CONCLUSION:

This experimental study showed no statistically significant differences in biomechanical performance between 1.8-mm ASAs and 2.9-mm SAs.

CLINICAL RELEVANCE:

Patellar fixation with 2 parallel ASAs may provide adequate patellar fixation for MPFL reconstruction, while their smaller diameter could potentially decrease the risks for patella fracture and violation of the articular surface in the cadaver model

Abstract:

PURPOSE:

To determine common mechanisms of anterior cruciate ligament (ACL) injury in baseball players and to quantify the rate of return to play after primary surgical reconstruction and review intermediate clinical outcomes.

METHODS:

Surgical injuries involving the ACL in youth, high school, collegiate, and professional baseball players were queried for an 11-year period (2001 to 2011). Over the study period, 42 baseball players were identified who had undergone arthroscopically assisted primary ACL reconstruction by 1 of 3 attending surgeons. Retrospective chart review was performed for all 42 patients to evaluate variables of age, level of competition, position, mechanism of injury, graft choice, and associated meniscal injuries. Twenty-six patients were reached for telephone survey and International Knee Documentation Committee questionnaire and they answered questions about their original injury and playing history.

RESULTS:

The most common mechanism of injury was fielding, followed by base running. Infielders and outfielders (32% each) were the most commonly injured position, followed by pitchers (29%). Among the 32 players for whom it could be determined, 30 (94%) were able to return to playing baseball at a mean follow-up of 4.2 years (range 1.0 to 9.9 years). The mean International Knee Documentation Committee score was 84.0 (range 63 to 91). Among the 26 patients contacted for telephone interview, no one required revision ACL surgery, but 3 required a subsequent procedure for meniscal tear. Twenty-five patients (96%) denied any episodes of instability in the knee after reconstruction.

CONCLUSIONS:

The overwhelming majority of baseball players that sustain ACL injuries do so while fielding or base running. Outfielders are significantly more likely than infielders to suffer ACL injuries while fielding versus base running. The results with respect to return to play are promising, as nearly all patients were able to return to baseball and none required a revision ACL surgery at a mean follow-up of 4.2 years.

LEVEL OF EVIDENCE:

Level IV, therapeutic case series

Abstract:

BACKGROUND:

Avulsion of the biceps femoris from the fibula and proximal tibia is encountered in clinical practice. While the anatomy of the primary posterolateral corner structures has been qualitatively and quantitatively described, a quantitative analysis regarding the insertions of the biceps femoris on the fibula and proximal tibia is lacking.

PURPOSE:

To quantitatively assess the insertions of the biceps femoris, fibular collateral ligament (FCL), and anterolateral ligament (ALL) on the fibula and proximal tibia as well as establish relationships among these structures and to pertinent surgical anatomy.

STUDY DESIGN:

Descriptive laboratory study.

METHODS:

Dissections were performed on 12 nonpaired, fresh-frozen cadaveric specimens identifying the biceps femoris, FCL, and ALL, and their insertions on the proximal tibia and fibula. The footprint areas, orientations, and distances from relevant osseous landmarks were measured using a 3-dimensional coordinate measurement device.

RESULTS:

Dissection produced 6 easily identifiable and reproducible anatomic footprints. Tibial footprints included the insertion of the ALL and an insertion of the biceps femoris (TBF). Fibular footprints included the insertion of the FCL, a distal insertion of the biceps femoris (DBF), a medial footprint of the biceps femoris (MBF), and a proximal footprint of the biceps femoris (PBF). The mean area of these footprints (95% CI) was as follows: ALL, 53.0 mm(2) (38.4-67.6); TBF, 93.9 mm(2) (72.0-115.8); FCL, 86.8 mm(2) (72.3-101.2); DBF, 119 mm(2) (91.1-146.9); MBF, 46.8 mm(2) (29.0-64.5); and PBF, 215 mm(2) (192.4-237.5). The mean distance (95% CI) from the Gerdy tubercle to the center of the ALL footprint was 24.3 mm (21.6-27.0) and to the center of the TBF was 22.5 mm (21.0-24.0). The center of the DBF was 8.68 mm (7.0-10.3) from the anterior border of the fibula, the center of the FCL was 14.6 mm (12.5-16.7) from the anterior border of the fibula and 20.7 mm (19.0-22.4) from the tip of the fibular styloid, and the center of the PBF was 8.96 mm (8.2-9.7) from the tip of the fibular styloid.

CONCLUSION:

A tibial footprint, distal fibular footprint, medial fibular footprint, and proximal fibular footprint were all consistent components of the insertion of the biceps femoris. Consistent relationships existed between the biceps femoris and insertions of the ALL and FCL.

CLINICAL RELEVANCE:

The size of these footprints and distances from pertinent surgical landmarks will guide repairs of biceps femoris avulsion injuries.

Abstract:

Braces designed to unload the more diseased compartment of the knee have been used to provide symptomatic relief from osteoarthritis (OA). Research on the efficacy of these braces is needed. Thirty-one patients with knee OA were randomized to receive an unloader brace (n = 16) or not to receive a brace (control group, n = 15). Knee Injury and Osteoarthritis Outcomes Score (KOOS) and visual analog scale (VAS) scores were used to evaluate outcomes. KOOS results showed that the brace group had significantly less pain (P < .001), fewer arthritis symptoms (P = .007), and better ability to engage in activities of daily living (P = .008). There was no difference in function in sport and recreation (P = .402) or in knee-related quality of life (P = .718). VAS results showed that the brace group had significantly less pain throughout the day (P = .021) and had improved activity levels (P = .035). There was no difference in ability to sleep (P = .117) or in use of nonsteroidal anti-inflammatory drugs (P = .138). Our study results showed that use of an unloader brace for medial compartment knee OA led to significant improvements in pain, arthritis symptoms, and ability to engage in activities.

Abstract:

This article aims to evaluate factors associated with chondral and meniscal lesions in primary and revision anterior cruciate ligament (ACL) reconstructions. ACL reconstructions from 2001 to 2008 at a single institution were retrospectively analyzed. Logistic regression was used to estimate the association between chondral and meniscal injuries and age, gender, tear chronicity, additional ligamentous injuries, sport type, and participation level. Of the 3,040 ACL reconstructions analyzed, 90.4% were primary reconstructions and 9.6% were revisions. Meniscal injuries were significantly lower in the revision group (44.0 vs. 51.9%; p = 0.01), while chondral injuries were significantly higher in the revision group (39.9 vs. 24.0%; p < 0.0001). Inspection of the small subgroup (n = 85) receiving both primary and revision ACL surgery at our center indicated that meniscal injuries at revision were evenly split between menisci with and without previous repairs, whereas the vast majority of Grade III and IV chondral lesions were new. More patients presented for surgery later in the revision group than in the primary group (56.5 vs. 35.3%; p < 0.0001). Male gender, primary reconstruction, and short interval (less than 2 weeks) between injury and surgery were associated with increased likelihood of meniscus tear. Age (greater than 22 years) and long interval (greater than 6 weeks) between injury to surgery and higher sport activity level were associated with chondral lesions. Revision ACL reconstructions are associated with a higher proportion of chondral lesions and a lower proportion of meniscal tears. Early primary and revision ACL construction is recommended to reduce the probability of chondral lesions.

Abstract:

The purpose of this study was to identify risk factors for revision surgery following primary anterior cruciate ligament (ACL) reconstruction. Methods A retrospective analysis of 2,965 patients who underwent a primary ACL reconstruction were separated into two groups: those who returned to our center for revision of their reconstruction (n = 67) and those who did not return to our center for revision of their reconstruction (n = 2,898). Patient characteristics assessed at the time of primary reconstruction include age, gender, graft type, graft source, meniscal and/or chondral injury, sport, side of effected extremity, level of competition, and surgeon. Multivariable analyses were performed to identify significant, independent associations with the need for revision. Results The portion of patients who returned for revision reconstruction after primary ACL reconstruction was 2.3% (67/2,965). Age (p < 0.001), sport type (p = 0.007), and level of participation (p < 0.001) were significantly different between the nonrevision and revision patients. Graft type preferences varied among surgeons (p < 0.001). Accounting for sport type or level of competition, age (p = 0.014) and surgeon (p = 0.041) were independently associated with revision. Gender, extremity (R vs. L), meniscal or chondral injury, and graft characteristics were not associated with revision. Conclusion Revision of primary ACL reconstructions is independently associated with age and choice of surgeon at the time of primary reconstruction.

Abstract:

BACKGROUND:

The number of adolescent anterior cruciate ligament (ACL) injuries is rising with increased participation in higher level athletics at earlier ages. With an increasing number of primary ACL reconstructions (ACLRs) comes a rise in the incidence of revision ACLRs.

PURPOSE:

To evaluate the clinical results of revision ACLR across a group of high-level adolescent athletes with at least 2-year follow-up.

STUDY DESIGN:

Case series; Level of evidence, 4.

METHODS:

A retrospective review of 21 adolescent athletes (age range, 10-19 years) who underwent revision ACLR with at least 2-year follow-up was conducted. Patient-reported outcome measures (PROMs) included the International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form, Lysholm knee scoring scale, Tegner activity level scale, and modified Cincinnati Knee Rating System. Return to sport (RTS) and overall patient satisfaction were also assessed.

RESULTS:

The mean age at the time of surgery was 16.5 years (range, 14-19 years), and the mean follow-up was 46.4 months (range, 24-97 months); 42.9% of patients were female, and 52.4% of patients participated in collision sports. The mean time to failure after primary ACLR was 13.1 ± 8.0 months, and the most common mechanism of failure was noncontact in at least 66.7% of cases. The revision graft type included bone-patellar tendon-bone (BPTB) in 71.4% of cases; 26.7% of BPTB grafts were from the contralateral extremity. Concomitant procedures were performed for intra-articular lesions in 71.4% of patients. The mean patient satisfaction rate was 95.3%. There were 3 cases of a graft reinjury at a mean of 25 months postoperatively. The mean PROM scores were as follows: IKDC, 87.5 ± 12.7; Tegner, 7.2 ± 2.0; Lysholm, 93.7 ± 9.8; and Cincinnati, 93.4 ± 10.0. Of those attempting to RTS, 68.4% of patients successfully returned at the same level of competition. Patients with a lateral compartment chondral injury were less likely to RTS (P < .05). Independent variables shown to have no significant relationship to PROMs or RTS included age, follow-up, sport classification, associated meniscal tears, revision graft size/type, and concomitant procedures.

CONCLUSION:

Revision ACLR can be an effective surgical option in adolescents participating in collision and contact sports, with good to excellent subjective outcome scores. At a minimum 2-year follow-up, a graft rupture after revision ACLR occurred in 14% of cases. Of the athletes attempting to RTS, 68.4% returned to their preinjury level of competition.

Abstract:

Arthroscopic education research recently has been focused on the use of skills labs to facilitate resident education and objective measure development to gauge technical skill. This study evaluates the effectiveness of three different teaching methods. Medical students were randomized into three groups. The first group received only classroom-based lecture. The second group received the same lecture and 28 minutes of lab-based hands-off arthroscopy instruction using a cadaver and arthroscopy setup. The final group received the same lecture and 7 minutes of hands-on arthroscopy instruction in the lab on a cadaver knee. The arthroscopic knee exam that followed simulated a diagnostic knee exam and subjects were measured on task completion and by the number of look downs. The number of look downs and the number of tasks completed did not achieve statistical significance between groups. Posttest survey results revealed that the hands-on group placed significantly more value on their educational experience as compared with the other two groups. (Journal of Surgical Orthopaedic Advances.

Abstract:

OBJECTIVE:

To describe and validate a technique for sonographically guided posterior cruciate ligament (PCL) injections.

DESIGN:

Prospective, cadaveric laboratory investigation.

SETTING:

Procedural skills laboratory.

SUBJECTS:

Eight unembalmed, cadaveric, mid-thigh-knee specimens (4 left knees and 4 right knees) obtained from 4 male and 4 female donors aged 57 to 64 years (mean 60.8 years) with body mass indices of 27.7 to 36.5 kg/m(2) (mean 32 kg/m(2)).

METHODS:

A 5-2-MHz curvilinear probe and a 22-gauge, 78-mm stainless steel needle was used to inject 2 mL of diluted blue latex into the PCL of each specimen using an in-plane, caudad-to-cephalad approach. At a minimum of 24 hours postinjection, each specimen was dissected to assess the presence and distribution of latex within the PCL.

MAIN OUTCOME:

Presence and distribution of latex within the PCL.

RESULTS:

All 8 injections accurately delivered latex throughout the PCL, including the tibial and femoral footprints. In 2 of 8 specimens (25%), a small amount of latex was noted to extend beyond the PCL and into the joint space. No specimens exhibited evidence of needle injury of latex infiltration with respect to the popliteal neurovascular bundle, menisci, hyaline cartilage, or anterior cruciate ligament.

CONCLUSIONS:

Sonographically guided intraligamentous PCL injections are technically feasible and can be performed with a high degree of accuracy. Sonographically guided PCL injections should be considered for research and clinical purposes to deliver therapeutic agents into the PCL postinjury or postreconstruction

Abstract:

OBJECTIVE:

To describe and validate a practical technique for sonographically guided anterior cruciate ligament (ACL) injections.

DESIGN:

Prospective, cadaveric laboratory investigation.

SETTING:

Procedural skills laboratory in a tertiary medical center.

SUBJECTS:

Ten unembalmed, cadaveric mid-thigh-knee-ankle foot specimens (5 left knees and 5 right knees; 5 male and 5 female) from 10 donors aged 76 to 93 years (mean 85.6 years) with body mass indices of 17.6 to 42.2 kg/m(2) (mean 28.8 kg/m(2)).

METHODS:

A single, experienced operator used a 22-gauge, 63.5-mm stainless steel needle and a 12-3-MHz linear transducer to inject 1.5 mL of diluted colored latex into the ACLs of 10 unembalmed cadaveric specimens via an in-plane, caudad-to-cephalad approach, long axis to the ACL. At a minimum of 24 hours postinjection, specimens were dissected, and the presence and distribution of latex within the ACL assessed by a study co-investigator.

MAIN OUTCOME:

Presence and distribution of latex within the ACL.

RESULTS:

All 10 injections accurately delivered latex into the proximal (femoral), midsubstance, and distal (tibial) portions of the ACL. No specimens exhibited evidence of needle injury or latex infiltration with respect to the menisci, hyaline cartilage, or posterior cruciate ligament.

CONCLUSIONS:

Sonographically guided intra-ligamentous ACL injections are technically feasible and can be performed with a high degree of accuracy. Sonographically guided ACL injections could be considered for research and clinical purposes to directly deliver injectable agents into the healing ACL postinjury or postreconstruction.

Abstract:

Obesity is the primary risk factor for the development and progression of medial compartment knee osteoarthritis. Laterally wedged insoles can reduce many of the biomechanical risk factors for disease development in osteoarthritis patients and lean individuals but their efficacy is unknown for at-risk, obese women. The purpose was to determine how an 8° laterally wedged insole influenced kinetic and kinematic gait parameters in obese women. Gait analysis was performed on fourteen obese (average 29.3 years; BMI 37.2kg/m(2)) and 14 lean control women (average 26.1 years; BMI 22.4kg/m(2)) with and without a full-length, wedged insole. Peak joint angles, the external knee adduction moment and its angular impulse were calculated during preferred and standard 1.24m/s walking speeds. Statistical significance was assessed using a 2-way ANOVA (α=0.05). The insole significantly reduced the peak external knee adduction moment (mean decrease of 3.6±3.9Nm for obese and 1.9±1.8Nm for controls) and its angular impulse in both groups. The wedged insoles also produced small changes in ankle dorsiflexion (obese: 1.2±1.4° increase; control: 1.5±1.4° increase) and eversion range of motion (obese: 1.3±1.9° decrease; control: 1.5±1.2° decrease) but did not alter peak angles of superior joints. Although the majority of obese women may develop knee osteoarthritis during their lifetime, a prophylactic insole intervention could allow obese women with no severe knee malalignments to be active while preventing or delaying disease onset. However, the long-term effects of the insole have not yet been examined.

Abstract:

BACKGROUND:

The JOURNEY II Bi-Cruciate Stabilizing Total Knee System (BLINDED) is a second-generation guided-motion knee implant that has been used in over 100,000 primary total knee arthroplasties (TKAs) worldwide. However, performance information is limited.

METHODS:

Data for 2059 primary TKAs were abstracted at 7 US and 3 European sites. Estimates of cumulative incidence of revision were compared with registry data for cemented posterior-stabilized implants.

RESULTS:

Average age was 64.3 years (range, 18-91); 58.5% were females; and 12.3% TKAs were in subjects younger than 55 years. Patellae were resurfaced in 95.9%. Median time since primary TKA was 4.2 years; longest was 6.1 years; and 78.9% were 3 years or more since primary TKA. Of 67 revisions (3.2%), 20 (30%) involved femoral or tibial component removal compared to 42% in the Australian Joint Registry (Australian Orthopedic Association National Joint Replacement Registry). All-component revisions accounted for 15 of 67, femoral component only for 2 of 67, tibial component only for 3 of 67, patellar component with/without tibial insert exchange for 17 of 67, and isolated tibial insert exchange for 30 of 67. In addition, there were 18 reoperations without component exchange. Component revision indications were infection (33%), mechanical loosening (21%), fracture of bone around the joint (16%), and instability (15%). Kaplan-Meier revision estimate was 3.1 and 3.6 per 100 TKAs at 3 and 5 years, respectively, compared to Australian Orthopedic Association National Joint Replacement Registry estimates of 3.1 and 4.1 per 100 TKAs.

CONCLUSION:

The revision rate for the second-generation implant was similar to cemented posterior-stabilized registry controls.

Abstract:

PURPOSE:

The purpose of this study was to compare cruciate ligament forces between the forward lunge with a short step (forward lunge short) and the forward lunge with a long step (forward lunge long).

METHODS:

Eighteen subjects used their 12-repetition maximum weight while performing the forward lunge short and long with and without a stride. EMG, force, and kinematic variables were input into a biomechanical model using optimization, and cruciate ligament forces were calculated as a function of knee angle. A two-factor repeated-measure ANOVA was used with a Bonferroni adjustment (P < 0.0025) to assess differences in cruciate forces between lunging techniques.

RESULTS:

Mean posterior cruciate ligament (PCL) forces (69-765 N range) were significantly greater (P < 0.001) in the forward lunge long compared with the forward lunge short between 0 degrees and 80 degrees knee flexion angles. Mean PCL forces (86-691 N range) were significantly greater (P < 0.001) without a stride compared with those with a stride between 0 degrees and 20 degrees knee flexion angles. Mean anterior cruciate ligament (ACL) forces were generated (0-50 N range between 0 degrees and 10 degrees knee flexion angles) only in the forward lunge short with stride.

CONCLUSIONS:

All lunge variations appear appropriate and safe during ACL rehabilitation because of minimal ACL loading. ACL loading occurred only in the forward lunge short with stride. Clinicians should be cautious in prescribing forward lunge exercises during early phases of PCL rehabilitation, especially at higher knee flexion angles and during the forward lunge long, which generated the highest PCL forces. Understanding how varying lunging techniques affect cruciate ligament loading may help clinicians prescribe lunging exercises in a safe manner during ACL and PCL rehabilitation.

Abstract:

PURPOSE:

To evaluate the accuracy of Blumensaat’s line (BL) in predicting the tendinous graft length and tibial tunnel length (TTL) in an independent-tunnel anterior cruciate ligament reconstruction (ACLR) using a bone-patellar tendon-bone (BTB) allograft.

METHODS:

Eighteen ACLRs were performed on cadaveric specimens using an anteromedial portal technique. All knees had no previous surgeries or deformities. Lateral knee radiographs of each specimen were taken prior to the ACLR, and BL was measured. Length-specific allografts for the tendinous portion of the grafts were then ordered by adding 20 mm to the length of BL. The TTL was predicted by subtracting BL and femoral tunnel length (FTL) from the overall graft length. Graft-tunnel mismatch (GTM) was recorded for each specimen. Statistical analysis compared overall results with the gold standard (0 mm) of GTM.

RESULTS:

The average lateral femoral condyle width measured in line with the femoral tunnel was 33 ± 3.43 mm. The average FTL was 25 ± 0.54 mm. The average intra-articular distance (IAD) between femoral and tibial tunnel apertures was 31 ± 3.65 mm. The average TTL was 35 ± 2.21 mm. The difference between the predicted TTL and the actual TTL was not statistically significant (P = .3). The mean GTM was -0.9 ± 3.15 mm. There was no statistically significant difference between the BL method and the gold standard (P = .45). The mean percent difference between BL and the IAD was 5.2%.

CONCLUSIONS:

The BL method can accurately predict the desired length for the tendinous portion of a BTB allograft as well as the TTL, thereby potentially minimizing GTM during arthroscopic BTB allograft ACLR. Patient-specific allografts can be ordered preoperatively based on BL.

CLINICAL RELEVANCE:

This method provides the surgeon a way to avoid GTM preoperatively by ordering patient-specific grafts prior to performing an independent-tunnel BTB allograft ACLR.

Abstract:

We report a patient who developed persistent knee pain with mechanical symptoms after an uncomplicated patellofemoral arthroplasty. The etiology of his knee pain remained inconclusive following magnetic resonance imaging due to metallic artifact image distortion. With the use of an in-office needle arthroscopy, an immediate and definitive diagnosis was obtained, preventing an unnecessary surgery for a diagnostic arthroscopy. We discovered a lateral meniscus tear, an anterior cruciate ligament tear, and a medial femoral condyle chondral defect for which the patient underwent arthroscopic partial meniscectomy, ligament reconstruction, and osteochondral allograft transplantation, with resolution of his knee pain.

Abstract:

BACKGROUND:

Although patients considered “successful” at longer-term follow-up no longer exhibited patellar instability, those with more severe malalignment issues had other, gradually worsening symptoms such as activity-related pain, crepitation, swelling with activities, and pain with weather changes.

HYPOTHESIS:

Improvement of patellar tracking by correction of the tubercle-sulcus angle and related ligament deficiencies will result in good to excellent results, regardless of the technique employed.

STUDY DESIGN:

Cohort study; Level of evidence, 3.

METHODS:

Twenty-five patients with dislocating patellae and significant lower leg deformity were treated; 12 patients (group 1) underwent a derotational high tibial osteotomy and 13 patients (group 2) underwent an Elmslie-Trillat-Fulkerson proximal-distal realignment. All were prospectively evaluated a minimum of 24 months postoperatively with a physical examination, validated outcome questionnaires, radiographs, and computerized axial tomography scans. Postoperative 3-dimensional bilateral gait analyses were performed on all subjects walking on a 3-dimensional force treadmill to measure stance kinematics, foot progression angle, knee flexion, knee valgus-varus, hip flexion, and patella angle. Contralateral limbs with similar preoperative alignment were used as controls.

RESULTS:

Group 1 patients significantly improved over their preoperative status in all primary subjective and functional outcome parameters, and were significantly better than group 2 patients. Group 2 patients improved, but not to the degree of group 1 patients. Gait analysis revealed group 1 patients had more symmetrical gait patterns, with less variability and less compensatory gait changes, than group 2 patients.

CONCLUSION:

The original hypothesis proved to be incorrect. The simultaneous correction of ligament imbalance, excessive tubercle-sulcus angle, and lower limb torsional deformity produced significantly better results than conventional proximal-distal realignment.