The incidence and clinical outcomes of peroneal nerve injuries associated with posterolateral corner injuries of the knee.

PURPOSE: The purpose of the study was to investigate the incidence of complete and partial peroneal nerve injuries in patients with posterolateral corner (PLC) knee injuries; additionally, to compare patient-reported outcomes among patients with and without peroneal nerve injury and to examine the factors that predict the recovery of nerve function. METHODS: A retrospective chart review was performed to identify patients who underwent PLC reconstruction or repair from 2000 to 2012 with a minimum 6-month clinical follow-up. Peroneal nerve injuries were identified, and treatments and outcomes were analyzed. IKDC and KOOS outcome scores at the final follow-up were reported. RESULTS: There were 61 PLC injuries in 60 patients. Sixteen of the 61 knees (26.2%) had a peroneal nerve injury at initial presentation; there were 13 complete and 3 partial nerve injuries. The median age was 31 years (15 men and 1 woman) and 31 years (33 men and 12 women) in the nerve and non-nerve injury cohorts, respectively. The median follow-up in the nerve injury group was 26 months (interquartile range (IQR): 12-48), and in the non-nerve injury cohort (n.s.) 61 months (IQR 22-85). All 13 complete injuries were treated with neurolysis: 3 were complete transections and 10 were stretch injuries. Of the ten stretch injuries, five (50%) spontaneously recovered full nerve function at the final follow-up. The remaining six patients chose definitive treatment with ankle-foot orthoses. Two of the three transected nerve patients underwent successful posterior tibialis transfer, and one chose ankle-foot orthoses. All three partial nerve injuries underwent neurolysis and had complete nerve recovery at the final follow-up. The median IKDC scores in the nerve injury group and the non-nerve injury group were 64.4 (IQR 47.8-73.3) and 72.8 (IQR 59.3-87.9) (n.s.), respectively, and the median Lysholm scores were 85 (IQR 83-92) and 86.5 (IQR 79-90) (n.s.), respectively. There were no significant differences in the rates of complications, secondary surgeries, mechanism of injury, KDIII injuries, or other injuries. CONCLUSION: This study demonstrated comparable rates of peroneal nerve injuries in PLC injuries (26.2%) to that in the literature. The rates of nerve recovery for complete disrupted injury, complete stretched injury, and partial injury were 0, 50, and 100% with an overall rate of recovery of 50%. The outcome scores were similar between patients with and without nerve injuries; however, a small cohort size led to limitations in statistical analysis. Thus, a prolonged trial of non-operative treatment is recommended for peroneal nerve injuries to allow for assessment of nerve recovery and patient outcome before entertaining surgical treatments. LEVEL OF EVIDENCE: Level IV.

Can Competitive Athletes Return to High-Level Play After Osteochondral Allograft Transplantation of the Knee?

PURPOSE: To investigate functional outcomes among competitive athletes undergoing osteochondral allograft (OCA) transplantation of the knee, including rates of return to play (RTP), and factors preventing RTP. METHODS: A retrospective review identified all competitive athletes (high school, intercollegiate, professional) undergoing isolated femoral condyle OCA from 2004 to 2013. Patient-reported outcome (PRO) questionnaires (Lysholm, International Knee Documentation Committee [IKDC], Knee Injury and Osteoarthritis Outcome Score [KOOS], Western Ontario and McMasters Universities Arthritis Index [WOMAC], 12-Item Short Form Health Survey [SF-12], Tegner, and Marx) and custom RTP surveys were administered. All subsequent reoperations were documented. RESULTS: Thirteen athletes (4 intercollegiate, 9 high-school) were identified with an average follow-up of 5.9 ± 2.5 years. Seven athletes (54%) returned to competitive sport at an average of 7.9 ± 3.5 months, 5 of whom returned to preinjury functional levels. Of the 8 athletes who either did not return to competitive sport or failed to sustain their high level of play, the most common reasons cited were graduation from high school or college (4 patients, 50%) or fear of reinjury (3 patients, 38%). All 4 patients citing graduation as the primary factor preventing return to preinjury level of competitive sport resumed recreational sport without limitations, yielding an adjusted RTP rate of 10 patients (77%) who either returned to competitive play or believed they could return if they had not graduated. At final follow-up, athletes reported significant improvements in all PRO scores except for KOOS-Sport, WOMAC-Stiffness, and SF-12 Mental subscales. There were 3 reoperations at an average of 3.8 ± 3.3 years after the index OCA. There were no instances of graft failure. CONCLUSIONS: OCAs provide an adjusted RTP rate of 77% for high-level adolescent athletes. Social factors may be more likely than persistent pain to prevent return to sport. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Surgical treatment of multiligament knee injuries.

PURPOSE: To analyse one institution's experience with multiligament knee injuries. METHODS: Over 10 years, 133 multiligament knee injuries including 130 patients were included in the study. Inclusion criteria included: (1) injury to two or more knee ligaments (2) multiligament knee repair/reconstructive surgery. RESULTS: The average age at time of injury was 26 years old, and 76 % were male. Fifty-one (38 %) multiligament knee injuries had >2 ligaments injured. Peroneal injuries occurred in 26 patients (20 %), and four (3 %) had associated vascular injuries. A high energy mechanism of injury was noted in 39 %. Twenty-five per cent of patients had an additional orthopaedic injury and, 11.5 % suffered additional non-orthopaedic injuries. Definitive surgical intervention was performed acutely (<3 weeks) in 47 %. Ninety-one per cent of multiligament knee injuries underwent reconstruction with or without repair. Forty-three complications occurred in 37 patients. Patients who suffered >2 ligament injury or had surgery acutely were at an increased risk of knee stiffness requiring manipulation under anaesthesia (MUA) (p = 0.016 and p = 0.047, respectively). Knees with >2 ligaments injured were associated with higher post-operative complications (p = 0.007). Knee dislocation IV knees were at increased risk to undergo revision surgery (p = 0.041). Obese patients were more likely to have a post-operative infection (p = 0.038). Repair, reconstruction or type of graft used had no impact on need for revision surgery. CONCLUSIONS: Multiligament knee injured patients undergoing surgical intervention are a highly complex patient population. This study outlines the patient population, treatment, and complications of one academic institution over 10 years. Overall complications were higher in patients with >2 ligaments injured. Knee stiffness requiring MUA was more common in patients who had >2 ligaments ruptured and those treated acutely. Knees with all four ligaments injured were more likely to undergo revision surgery. LEVEL OF EVIDENCE: Retrospective case series, Level IV.

Age Differences in the Prevalence of Isolated Medial and Lateral Meniscal Tears in Surgically Treated Patients.

PURPOSE: To compare the prevalence of isolated lateral and medial meniscal tears in different aged populations. METHODS: A five-year retrospective review for meniscal procedures performed on a total of 782 patients. Each chart was reviewed to document the prevalence of medial or lateral meniscal injuries. Inclusion criteria were patients found to have documented evidence of meniscal tear, either lateral or medial, without any concomitant injuries and/or any other procedures performed. Patients excluded from the study were those with concomitant pathologies, such as chondromalacia, malalignment or ligamentous injuries. Patients were classified by age into three groups: < 20 years, 20-30 years and > 30 years old. RESULTS: 68.7% of patients had medial meniscal tears, (average age 37.6 years), 17.1% of these were isolated medial meniscus injuries (average 31.9 years). 31.3% had lateral meniscal injuries (average 27.7 years). Of these, 18.8 % had isolated lateral meniscal injuries (average 22.8 years). All remaining patients had additional diagnoses/procedures. Isolated medial meniscal injuries were more common in older patients as 48 of the 92 isolated medial tears (52.2%) were found in patients > 30 years of age (p <0.001). Isolated lateral meniscal injuries, on the other hand, were more common in younger patients. 29 of the 46 isolated lateral tears (63%) occurred in patients under 20 years (p = 0.002). Only seven (15.2%) isolated lateral tears were shown in patients older than 30 years. CONCLUSION: Isolated lateral meniscal tears are more common in patients < 20 years, and decrease with age, while the prevalence of medial meniscal tears increase with age.

Effectiveness of Lavage Techniques in Removing Immunogenic Elements from Osteochondral Allografts.

Objective This study aimed to compare standard saline lavage to combination saline and high-pressure carbon dioxide (CO2) lavage in removing marrow elements from osteochondral allografts. Design Six fresh hemicondyles were obtained. Three osteochondral allograft plugs (15-mm diameter, 6-mm depth) were harvested from each hemicondyle and randomized to 1 of 3 treatment arms: A, no lavage; B, 1 L standard saline lavage; C, simultaneous saline (1 L) and 1-minute high-pressure CO2 lavage. After hematoxylin and eosin staining, a "percentage fill" of remaining marrow elements was calculated for each overall sample and then repeated in 3 distinct compartments for each sample based on depth from surface: 1, deepest third; 2, middle third; and 3, most superficial third. Trial arms B and C were compared with 1-tailed Student t tests. Results Group A had an overall percentage fill of 51.2% ± 8.8%. While both lavage techniques decreased overall remaining marrow elements, group B yielded significantly higher percentages of remaining marrow elements than group C (28.6% ± 16.5%, 14.6% ± 8.7%, P = 0.045). On depth analysis, group A exhibited homogenous filling of trabecular space (63.0% ± 15.5%, 67.6% ± 13.7%, and 55.2% ± 10.1% in zones 1, 2, and 3, respectively). Both lavage arms equally removed marrow elements from superficial zone 3 (B, 17.4% ± 9.2%; C, 15.6% ± 12.4%, P = 0.41) and middle zone 2 (B, 30.2% ± 17.7%; C, 21.4% ± 15.5%, P = 0.18). However, group C lavage removed significantly more marrow elements in deep zone 1 than group B (29.7% ± 10.9%, 58.5% ± 25.2%, P = 0.01). Conclusion Combination saline and high-pressure CO2 lavage more effectively clears marrow elements from osteochondral allografts than saline alone.

Malalignment: A Requirement for Cartilage and Organ Restoration.

The treatment of combined knee pathology is a challenging problem that requires careful attention to all aspects of the underlying disease. This is true of the interplay among malalignment and meniscal or articular cartilage restoration in the knee. Optimal outcomes are contingent on a comprehensive preoperative evaluation of patient-specific factors (patient expectations, patient age, and activity level), as well as disease-specific factors of the knee. Surgical intervention for meniscal or chondral deficiencies without attention to malalignment will lead to inferior outcomes. The focus of this review is to highlight the importance of malalignment correction when treating meniscal and articular cartilage pathology. This objective will be accomplished by outlining the approach to the preoperative evaluation, discussing the indications for surgical intervention, reviewing the preferred surgical techniques for correcting coronal malalignment of the knee, and providing a discussion of clinical outcomes.

Medial Patella Subluxation: Diagnosis and Treatment.

Medial patella subluxation is a disabling condition typically associated with previous patellofemoral instability surgery. Patients often describe achy pain with painful popping episodes. They often report that the patella shifts laterally, which occurs as the medial subluxed patella dramatically shifts into the trochlear groove during early knee flexion. Physical examination is diagnostic with a positive medial subluxation test. Nonoperative treatment, such as focused physical therapy and patellofemoral stabilizing brace, is often unsuccessful. Primary surgical options include lateral retinacular repair/imbrication or lateral reconstruction. Prevention is key to avoid medial patella subluxation. When considering patellofemoral surgery, important factors include appropriate lateral release indications, consideration of lateral retinacular lengthening vs release, correct MPFL graft placement and tension, and avoiding excessive medialization during tubercle transfer. This review article will analyze patient symptoms, diagnostic exam findings and appropriate treatment options, as well as pearls to avoid this painful clinical entity.

Arthroscopic-assisted reduction and percutaneous fixation of tibial plateau fractures.

Tibial plateau fractures present a difficult range of fractures to treat. Arthroscopy allows for a less invasive option when compared with arthrotomy. Furthermore, visualization of the articular surface arthroscopically can allow for a precise reduction and assessment of any concomitant injuries to the articular cartilage and meniscus. By use of arthroscopy, unicondylar lateral plateaus were traditionally approached through a laterally based metaphyseal window. However, in carefully selected patients and fracture patterns, a medially based, arthroscopic-assisted approach can create long bony tunnels for subchondral support and allow for greater ease in fracture reduction. We present our technique using a medial approach for arthroscopic-assisted fixation of lateral tibial plateau fractures.

Arthroscopic Meniscal Root Repair Using a Ceterix NovoStitch Suture Passer.

Meniscal root injuries can compromise knee function and lead to early degenerative changes if not appropriately treated. Numerous techniques have been described; however, the technical difficulties in performing these repairs are well known. Furthermore, the relative strengths of various repair techniques have been examined. This article describes a single-working portal meniscal root repair technique using a double-locking loop suture configuration with a novel suture-passing device that offers a strong, reproducible repair construct.

Biomechanical evaluation of medial patellofemoral ligament reconstruction.

BACKGROUND: The medial patellofemoral ligament (MPFL) is the most frequently injured soft tissue structure following acute lateral patellar dislocation. MPFL reconstruction has become a popular option to restore patellar stability following lateral patellar dislocation due to the high incidence of recurrent instability following conservative management. Anatomic reconstruction of the MPFL minimizes graft length changes during full knee range of motion and restores patellar stability. MATERIALS & METHODS: Four fresh frozen cadaver specimens underwent biomechanical testing in a materials testing machine. With the knee fixed in 30° of flexion, the patella was translated laterally a distance of 10 mm and continuous force-displace- ment data was collected with the intact MPFL and again following a newly described MPFL reconstruction technique. Lateral force-displacement and stiffness data were calculated, allowing comparison between the intact and reconstructed MPFL. RESULTS: The average lateral restraining force provided by the intact MPFL was 10.6 ± 5.7, 36.6 ± 2.7, and 69.0 ± 5.9 N while the lateral restraining force following MPFL reconstruction was 0.4 ± 4.3, 50.3 ± 16.3, and 110.2 ± 17.5 N at 1, 5, and 10 mm of lateral displacement, respectively. CONCLUSION: Anatomic MPFL reconstruction displays similar lateral restraining force compared to the intact MPFL at low levels of lateral displacement. At higher levels of displacement, the reconstructed MPFL provides increased lateral restraining force compared to the intact MPFL, improving patellar stability in pathologic knees.

In vivo evaluation of a new surfactant polymer coating mimicking the glycocalyx of endothelial cells.

The purpose of this study was to demonstrate that a proprietary surfactant polymer (SP) coating does not adversely affect the hemodynamic performance of cardiopulmonary bypass (CPB) or gas exchange in oxygenators. The new coating was applied to a CPB circuit including cannulae, reservoir, oxygenator, and blood pump implanted into 12 pigs, divided into groups with either coated or noncoated pumps. CPB flow was maintained at a fixed level of approximately 2.4 L/min for 6 hours with full heparinization. Hemodynamic data and pump performance were recorded every hour, and blood samples were taken every 2 hours. After sacrifice, the CPB circuit and major organs were macroscopically examined. There was no significant difference in the oxygen transfer rate between the two groups. The coating did not adversely affect oxygenator inlet or outlet pressures. There was no significant difference between the two groups in microthrombi seen in the oxygenators. No thromboemboli were noted in the major organs on gross or histologic examination. In conclusion, this new SP coating did not decrease gas exchange performance, and its biocompatibility evaluations revealed no differences between coated and noncoated groups under aggressive heparin use.