Adding Lateral Retinacular Release to Medial Patellofemoral Ligament Reconstruction Fails to Demonstrate Clinical Benefit Compared With Isolated Medial Patellofemoral Ligament Reconstruction.

Purpose: To compare functional outcomes and failure rates between medial patellofemoral ligament (MPFL) reconstructions with and without lateral retinacular release (LRR) at minimum 1-year follow up. Methods: A retrospective review identified consecutive patients from 2013 to 2019 at a single center who met all of the following inclusion criteria: at least 1 confirmed patellar dislocation, patellar tilt (evidenced by tight retinaculum on operative examination or patellar tilt on radiographs), underwent either MPFL reconstruction alone or combined with LRR, had available preoperative documentation and imaging, and were at least 1 year out of surgery. Patients were excluded if they had previous surgery to the ipsilateral limb or had any concomitant procedure performed. Demographics and preoperative imaging were evaluated. Failure rates and functional outcome scores were obtained including Kujala, Patient-Reported Outcomes Measurement Information System, International Knee Documentation Committee, Single Assessment Numeric Evaluation, and Knee injury and Osteoarthritis Outcome Scores. Clinical failure was defined as revision MPFL reconstruction on the affected knee or at least 1 instance of postoperative patellar dislocation. Results: A total of 18 patients underwent isolated MPFL reconstruction (mean follow-up = 29.3 ± 8.3 months, range = 15.1-42.8 months), and 31 underwent MPFL reconstruction combined with LRR (mean follow up = 36.0 ± 11.3 months, range = 14.0-51.9 months). At final follow-up, there were no statistical differences between the isolated MPFL and MPFL combined with LRR cohorts for any of the functional outcome scores (P > .05 for all). At the time of final follow-up, no patients who underwent isolated MPFL and 19.3% (n = 6) or patients undergoing MPFL combined with LRR experienced clinical failure (P = .073), as defined by subsequent patellar dislocation or revision MPFL reconstruction. Of these, 2 patients underwent revision MPFL reconstructions with distal tubercle transfer for borderline abnormal TT:TG (i.e., >15 mm). Conclusions: MPFL reconstruction surgery combined with LRR failed to demonstrate significantly different functional outcome scores and failure rates compared with isolated MPFL reconstruction at minimum 1-year follow up. In addition, there were no differences in rates of achieving MCID between both groups. Level of Evidence: Level III, retrospective cohort study.

Occupational and Functional Outcomes following Patellofemoral Arthroplasty in U.S. Military Servicemembers.

The functional outcomes in patients undergoing patellofemoral arthroplasty (PFA) with high occupational demands have not been fully examined. This study assessed return to work and conversion to TKA rates following PFA in a young, military cohort. Patient demographics, pain scores, and surgical information were retrospectively collected for all active-duty military members who underwent PFA over a 4-year period. The data were then analyzed to calculate return to work, conversion to TKA, and perioperative complications rates. A total of 48 servicemembers with 60 total PFAs (36 unilateral, 12 bilateral) were included, with a mean follow up of 2.2 years. At the final follow-up, 83% of servicemembers returned to military service or completed their service obligation after PFA. Conversion to TKA occurred in three (6.2%) patients at an average of 2.4 years after PFA, resulting in a PFA annual revision rate of 2.3%. The mean numeric rating scale for pain improved from 4.9 ± 2.6 at baseline to 2.5 ± 2.0 postoperatively (p < 0.001). Servicemembers with at least one prior ipsilateral knee procedure had a significantly decreased odds ratio (OR) for both occupational outcome failure (OR, 0.03; 95% confidence interval [CI], 0-0.29) and overall failure (OR, 0.13; 95% CI, 0.02-0.78). At an average of 2 years following PFA, 83% of military members returned to duty, with a low rate of revision to TKA. Prior ipsilateral knee procedure decreased the probability of medical separation. LEVEL OF EVIDENCE: IV.

Occupational Outcomes and Revision Rates for Medial Unicondylar Knee Arthroplasty in U.S. Military Servicemembers.

This study evaluates return to work and revision rates for medial unicondylar knee arthroplasty (UKA) in a high-demand military cohort. Patient demographic and clinical variables were isolated from the medical records of active-duty military servicemembers with at least 2 years of postoperative follow-up and correlated with return to work, medial UKA survivorship, and perioperative complications. The medial UKA annual revision rate was calculated as the percentage of implants revised per observed component year. A total of 39 servicemembers underwent 46 primary medial UKAs (32 unilateral and 7 bilateral) with a mean follow-up of 3.9 (2.0-6.6) years. At a minimum of 2 years postoperatively, 33 (85%) servicemembers returned to military service or successfully completed their service obligation. Older servicemembers (odds ratio [OR] = 0.67; 95% confidence interval [CI]: 0.45, 0.99) had a significantly decreased OR for knee-related medical separation. Nine servicemembers (20%) had conversion to TKA at an average of 2.4 (range, 0.6-5.6) years with a medial UKA annual revision rate of 5%. When compared with Navy/Air Force, Army/Marine servicemembers had an increased TKA conversion rate (OR = 5.40; 95% CI: 1.13, 25.81). Older age decreased the likelihood of medical separation and Army/Marines service was the sole risk factor associated with conversion to TKA. The level of evidence is IV, therapeutic case series.

Cartilage Restoration of Bipolar Lesions Within the Patellofemoral Joint Delays Need for Arthroplasty: A Systematic Review of Rates of Failure.

PURPOSE: The purpose of the present review is to systematically review the available literature for failure rates and complications of cartilage restoration of bipolar chondral defects in the patellofemoral (PF) joint to assess the ability to treat these lesions without arthroplasty. METHODS: PubMed and MEDLINE databases were queried between 2000 to 2020 using the keywords "osteochondral" and "knee" and "microfracture," "autologous chondrocyte implantation (ACI)," or "transplantation." Patient selection included patients with bipolar chondral lesions of the patellofemoral joint that were treated with cartilage restoration procedures. Treatment of PF joints were reviewed for surgical indications/technique, rates of failure, defect characteristics, and time to failure. For the purposes of this study, failure was defined by each individual author on their respective studies. RESULTS: After screening 1,295 articles, there were 8 publications analyzed quantitatively and 10 articles analyzed both quantitatively and qualitatively. A total of 249 knees involved bipolar lesions of the patellofemoral joint. The weighted average age was 36.5 ± 10.4 years, and weighted average follow-up was 89.0 ± 31.7 months. There were failures in 0% to 50% of cases, revision procedures in 0% to 10% of cases, conversion to arthroplasty in in 0% to 50% of cases, and unsatisfactory outcome without revision in 0% to 8.3% of cases. The range in average failure rate was 0% to 50.0% (I2 = 68.0%), whereas the range in average time to failure was 2.9 to 6.8 years (I2 = 79.0%). CONCLUSION: From the available data, established cartilage restoration procedures may provide favorable patient-reported function, avoidance of secondary surgery, and joint preservation in at least 80% of patients at short- to mid-term follow-up. LEVEL OF EVIDENCE: Level IV, systematic review of Level IV studies.

Cartilage Restoration for Tibiofemoral Bipolar Lesions Results in Promising Failure Rates: A Systematic Review.

PURPOSE: The purpose of the present study is to systematically review the available literature for management of bipolar lesions within the tibiofemoral joint and determine whether tibiofemoral cartilage restoration is an effective treatment modality. METHODS: PubMed and MEDLINE databases were queried between 2000 and 2020 using the following keywords: "osteochondral" and "knee" and "microfracture," "autologous chondrocyte implantation (ACI)," or "transplantation." Articles were reviewed for the presence of a bipolar or "kissing" tibiofemoral lesion and reported lesion size, concomitant procedures, failure rates, and time to failure. RESULTS: After screening 1,295 articles, there were 4 articles available for analysis and a total of 152 knees involving the management of bipolar tibiofemoral lesions. Age ranged from 14 to 60 years, and mean follow-up was between 12 and 240 months. There was 1 retrospective cohort study (36 knees) and 3 case series (mean, 38.7 ± 17.5 knees). There were 58 knees treated with bipolar osteochondral allograft (OCA) transplantation, 58 knees treated with bipolar ACI, 20 knees treated with femoral OCA and tibial debridement, and 16 knees treated with femoral OCA and tibial microfracture. There were 37 failures (24.3%): 16 patients (10.5%) were converted to unicompartmental or total knee arthroplasty, 4 restorative procedures (2.6%) were revised, and 8 patients (1.6%) had unsatisfactory outcomes only. The remaining 15 failures (9.9%) had an unspecified combination of objective failure. The mean rate of failure ranged between 0% and 44.1% (I 2 = 83.2%). The mean time to failure ranged between 2.7 and 4.1 years (I 2 = 79.1%). CONCLUSIONS: Cartilage restoration, through both ACI and OCA, had failure rates between 0% and 44% in patients with bipolar lesions of the tibiofemoral compartment. Although a higher level of evidence is required to prove efficacy, the current study demonstrates midterm survivorship rates between 55% and 100%, which may delay the need for secondary arthroplasty. LEVEL OF EVIDENCE: Level IV, systematic review of Level IV studies.