Background Patellofemoral instability affects activities of daily living and hinders athletic participation. Over the past 2 decades more attention has been paid to medial patellofemoral ligament reconstruction (MPFL) for treatment of recurrent patellar dislocations/subluxations. Numerous techniques have been reported; however, there is no consensus regarding optimal reconstruction. Purpose This study sought to report on the various techniques for MPFL reconstruction described in the literature and to assess the rate of complications associated with the procedure. Study Design Meta-analysis. Methods A systematic review of the literature was performed in early October 2010 using keywords “medial patellofemoral ligament,” “MPFL”, “reconstruction,” “complication(s),” and “failure(s)”. Articles meeting the inclusion criteria were reviewed. Graft choice, surgical technique, outcome measures, and complications were recorded and organized in a database. Descriptive statistical analysis was performed on the data collected. Results Twenty-five articles were identified and reviewed. A total of 164 complications occurred in 629 knees (26.1%). These adverse events ranged from minor to major including patella fracture, failures, clinical instability on post-operative examination, loss of knee flexion, wound complications, and pain. Twenty-six patients returned to the operating room for additional procedures. Conclusions Medial patellofemoral ligament reconstruction has a high rate of success for patients with patellofemoral instability; however, the complication rate of 26.1% associated with this procedure is not trivial. This study quantified complications and documented the variety of complications reported in outcomes-based literature.

Purpose The purpose of this study is to evaluate the effect of graft size on patient-reported outcomes and revision risk following ACL reconstruction. Methods A retrospective chart review of prospectively collected cohort data, 263 of 320 consecutive patients (82.2%) undergoing primary ACL reconstruction with hamstring autograft were evaluated. Graft size, femoral tunnel drilling technique, patient age, sex, and BMI at the time of ACL reconstruction, pre-operative and 2-year post-operative KOOS and IKDC scores, and whether each patient underwent revision ACL reconstruction during the 2 year follow-up period were recorded. Revision was used as a marker for graft failure. The relationship between graft size and patient-reported outcomes was determined by multiple linear regression. The relationship between graft size and risk of revision was determined by dichotomizing graft size at 8mm and stratifying by age. Results After controlling for age, sex, operative side, surgeon, BMI, graft choice, and femoral tunnel drilling technique, a 1 mm increased in graft size was noted to correlate with 3.3-point increase in the KOOS-pain subscale (p = 0.003), a 2.0-point increased in the KOOS activities of daily living subscale (p = 0.034), a 5.2-point increase in the KOOS-sport/recreation function subscale (p = 0.004), and a 3.4-point increase in the subjective IKDC score (p = 0.026). Revision was required in 0 of 64 patients (0.0%) with grafts greater than 8mm in diameter and 14 of 199 patients (7.0%) with 8 mm or smaller grafts (p = 0.037). Among patients age 18 and under, revision was required in 0 of 14 patients (0.0%) with grafts greater than 8mm in diameter and 13 of 71 patients (18.3 %) with 8 mm or smaller grafts. Conclusions Smaller hamstring autograft size is a predictor of poorer KOOS Sport and Recreation function 2 years following primary ACL reconstruction. Larger sample size is required to confirm the relationship between graft size and risk of revision ACL reconstruction. Level of Evidence Level 3

Cartilage repair or restoration in the knee provides short-term success with microfracture, autologous chondrocyte implantation, or osteochondral autograft. There are patient-specific and defect-specific factors that influence clinical outcomes.

Systematic reviews or meta-analyses critically appraise and formally synthesize the best existing evidence to provide a statement of conclusion that answers specific clinical questions. Readers and reviewers, however, must recognize that the quality and strength of recommendations in a review are only as strong as the quality of studies that it analyzes. Thus, great care must be used in the interpretation of bias and extrapolation of the review's findings to translation to clinical practice. Without advanced education on the topic, the reader may follow the steps discussed herein to perform a systematic review.

Full-thickness focal chondral defects in the knee are more common in athletes than among the general population. More than one-half of asymptomatic athletes have a full-thickness defect. Further study is needed to define more precisely the prevalence of these lesions in this population.