Diane L. Dahm

Surgery versus Physical Therapy for a Meniscal Tear and Osteoarthritis

BACKGROUND Whether arthroscopic partial meniscectomy for symptomatic patients with a meniscal tear and knee osteoarthritis results in better functional outcomes than nonoperative therapy is uncertain. METHODS We conducted a multicenter, randomized, controlled trial involving symptomatic patients 45 years of age or older with a meniscal tear and evidence of mild-to-moderate osteoarthritis on imaging. We randomly assigned 351 patients to surgery and postoperative physical therapy or to a standardized physical-therapy regimen (with the option to cross over to surgery at the discretion of the patient and surgeon). The patients were evaluated at 6 and 12 months. The primary outcome was the difference between the groups with respect to the change in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) physical-function score (ranging from 0 to 100, with higher scores indicating more severe symptoms) 6 months after randomization. RESULTS In the intention-to-treat analysis, the mean improvement in the WOMAC score after 6 months was 20.9 points (95% confidence interval [CI], 17.9 to 23.9) in the surgical group and 18.5 (95% CI, 15.6 to 21.5) in the physical-therapy group (mean difference, 2.4 points; 95% CI, -1.8 to 6.5). At 6 months, 51 active participants in the study who were assigned to physical therapy alone (30%) had undergone surgery, and 9 patients assigned to surgery (6%) had not undergone surgery. The results at 12 months were similar to those at 6 months. The frequency of adverse events did not differ significantly between the groups. CONCLUSIONS In the intention-to-treat analysis, we did not find significant differences between the study groups in functional improvement 6 months after randomization; however, 30% of the patients who were assigned to physical therapy alone underwent surgery within 6 months. (Funded by the National Institute of Arthritis and Musculoskeletal and Skin Diseases; METEOR ClinicalTrials.gov number, NCT00597012.).

The Influence of Obesity on the Complication Rate and Outcome of Total Knee Arthroplasty: A Meta-Analysis and Systematic Literature Review

BACKGROUND The increase in the number of individuals with an unhealthy high body weight is particularly relevant in the United States. Obesity (body mass index ≥ 30 kg/m2) is a well-documented risk factor for the development of osteoarthritis. Furthermore, an increased prevalence of total knee arthroplasty in obese individuals has been observed in the last decades. The primary aim of this systematic literature review was to determine whether obesity has a negative influence on outcome after primary total knee arthroplasty. METHODS A search of the literature was performed, and studies comparing the outcome of total knee arthroplasty in different weight groups were included. The methodology of the included studies was scored according to the Cochrane guidelines. Data extraction and pooling were performed. The weighted mean difference for continuous data and the weighted odds ratio for dichotomous variables were calculated. Heterogeneity was calculated with use of the I2 statistic. RESULTS After consensus was reached, twenty studies were included in the data analysis. The presence of any infection was reported in fourteen studies including 15,276 patients (I2, 26%). Overall, infection occurred more often in obese patients, with an odds ratio of 1.90 (95% confidence interval [CI], 1.46 to 2.47). Deep infection requiring surgical debridement was reported in nine studies including 5061 patients (I2, 0%). Deep infection occurred more often in obese patients, with an odds ratio of 2.38 (95% CI, 1.28 to 4.55). Revision of the total knee arthroplasty, defined as exchange or removal of the components for any reason, was documented in eleven studies including 12,101 patients (I2, 25%). Revision for any reason occurred more often in obese patients, with an odds ratio of 1.30 (95% CI, 1.02 to 1.67). CONCLUSIONS Obesity had a negative influence on outcome after total knee arthroplasty.

A Meta-analysis of Patellar Tendon Autograft Versus Patellar Tendon Allograft in Anterior Cruciate Ligament Reconstruction

PURPOSE Studies have suggested good long-term success rates with bone-patellar tendon-bone (BPTB) autograft and BPTB allograft in anterior cruciate ligament (ACL) reconstruction, but the numbers reported in available prospective studies may be underpowered to elucidate significant differences between the two groups. Here, we present a meta-analysis to compare the results of BPTB autograft and BPTB allograft in primary ACL reconstruction. METHODS A systematic review of prospective trials using BPTB autograft and BPTB allograft tissue for ACL reconstruction with a minimum 2-year follow-up was performed. Summary odds ratios (ORs), confidence intervals, and P values were calculated. RESULTS Of 548 studies, 6 fulfilled our inclusion criteria, with 256 patients in the autograft and 278 patients in the allograft group. Allograft patients were more likely to rupture their graft than autograft patients (OR, 5.03; P = .01) and more likely to have a hop test less than 90% of the nonoperative side (OR, 5.66; P < .01). When irradiated and chemically processed grafts were excluded from analysis, no significant differences were found between allograft and autograft patients with respect to graft rupture, rate of reoperation, normal/near normal IKDC scores, Lachman exam, pivot shift exam, patellar crepitus, hop test, or return to sport. CONCLUSIONS In this meta-analysis, ACL reconstruction with BPTB autograft was favored over BPTB allograft for graft rupture and hop test parameters. However, when irradiated and chemically processed grafts were excluded, results were not significantly different between the two graft types. LEVEL OF EVIDENCE Level III, systematic review of prospective nonrandomized cohort studies.

A Systematic Review of Anterior Cruciate Ligament Reconstruction with Autograft Compared with Allograft

BACKGROUND Anterior cruciate ligament reconstruction can be performed with use of either autograft or allograft tissue. It is currently unclear if the outcomes of these two methods differ significantly. This systematic review and meta-analysis investigated whether the short-term clinical outcomes of anterior cruciate reconstruction with allograft were significantly different from those with autograft. METHODS A computerized search of the electronic databases MEDLINE and EMBASE was conducted. Only therapeutic studies with a prospective or retrospective comparative design were considered for inclusion in the present investigation. Two reviewers independently assessed the methodological quality and extracted relevant data from each included study. If a study failed the qualitative assessment and statistical tests of homogeneity, it was excluded from the meta-analysis. Furthermore, a study was withdrawn from the meta-analysis of a particular outcome if that outcome was not studied or was not reported adequately. A Mantel-Haenszel analysis utilizing a random-effects model allowed for pooling of results according to graft source while accounting for the number of subjects in individual studies. RESULTS Nine studies were determined to be appropriate for the systematic review. Eight studies compared bone-patellar tendon-bone grafts, and one study compared quadruple-stranded hamstring grafts. Five studies were prospective comparative studies, and four were retrospective comparative studies. One study, which investigated allografts that underwent a unique sterilization process, demonstrated an allograft failure rate of 45% (thirty-eight of eighty-five). That study failed the qualitative assessment and statistical tests of homogeneity and consequently was excluded from the meta-analysis. When the outcomes from the remaining studies were pooled according to graft source, the meta-analyses of the Lysholm score, instrumented laxity measurements, and the clinical failure rate estimated mean differences and odds ratios that were not significant. These findings were robust during the sensitivity analysis, which varied the included studies or variables on the basis of graft type, instrumented laxity cut-off value, secondary sterilization technique, duration of follow-up, mean patient age, and study methodology. CONCLUSIONS In general, the short-term clinical outcomes of anterior cruciate reconstruction with allograft were not significantly different from those with autograft. However, it is important to note that none of these nonrandomized studies stratified outcomes according to age or utilized multivariable modeling to mathematically control for age (or any other possible confounder, such as activity level, that is not equally distributed in the two treatment groups). Understanding these limitations of the best available evidence, the surgeon may incorporate the results of the present systematic review into the informed-consent and shared-decision-making process in order to individualize optimum patient care.

Repair Versus Reconstruction of the Fibular Collateral Ligament and Posterolateral Corner in the Multiligament-Injured Knee

Background Treatment of the multiligament-injured knee remains controversial. Purpose To compare clinical and functional outcomes of a consecutive series of multiligament-injured knees that underwent repair of the fibular collateral ligament (FCL) and posterolateral corner (PLC), followed by delayed cruciate ligament reconstructions, with those that had single-stage multiligament reconstruction. Study Design Cohort study; Level of evidence, 3. Methods Patients with multiligament knee injury treated by a single surgeon were identified in our prospective database. Between February 2004 and May 2005, patients underwent repair of medial- and lateral-sided injuries, followed by delayed cruciate ligament reconstructions. Between May 2005 and February 2007, patients underwent single-stage multiligament knee reconstruction. All patients followed a standard rehabilitation protocol. Inclusion criteria were minimum 2-year follow-up and multiligament knee injury including the FCL/PLC. International Knee Documentation Committee subjective and Lysholm scores and objective clinical data were documented. Results We identified 45 knees (42 patients); 17 knees (14 patients) were excluded, leaving 28 knees (28 patients) in the study. The repair/staged group (10 knees in 10 patients) had a mean follow-up of 34 months (range, 24-49 months). The reconstruction group (18 knees in 18 patients) had a mean follow-up of 28 months (range, 24-41 months). Four of the 10 FCL/PLC repairs (40%) and 1 of the 18 FCL/PLC reconstructions (6%) failed (P = .04). After revision reconstructions, there were no statistically significant differences between mean International Knee Documentation Committee subjective scores (79 vs. 77, P = .92) and mean Lysholm scores (85 vs 88, P = .92). Regression analysis showed no effect on failure based on age, sex, injury mechanism, time to surgery, interval between stages, total number of ligaments injured, or location of tear. Conclusion Our series demonstrated a statistically significant higher rate of failure for repair compared with reconstruction of the FCL/PLC. Reconstruction of the FCL/PLC structures is a more reliable option than repair alone in the setting of a multiligament knee injury.

Predictors of Recurrent Instability After Acute Patellofemoral Dislocation in Pediatric and Adolescent Patients

Background: Patellofemoral instability is common in the pediatric and adolescent population, yet prognosis after the first dislocation has been difficult to determine. Purpose: To describe the demographics of pediatric and adolescent patients with a first-time patellofemoral dislocation and to determine predictors of recurrent instability. Study Design: Case-control study; Level of evidence, 3. Methods: A search of the Mayo Medical Index database between 1998 to 2010 was performed, and 2039 patients were identified. Inclusion criteria were (1) age 18 years or younger, (2) no history of patellofemoral subluxation/dislocation of the affected knee, (3) radiographs within 4 weeks of the initial instability episode, and (4) a dislocated patella requiring reduction or convincing history/findings suggestive of acute patellar dislocation (effusion/hemarthrosis, tenderness along medial parapatellar structures, and apprehension with lateral patellar translation). Radiographs were evaluated for trochlear dysplasia (Dejour classification) and patella alta (Caton-Deschamps and Insall-Salvati indices). Skeletal maturity was graded based on the distal femoral and proximal tibial physes (open, closing, or closed). Results: A total of 222 knees (120 male [54.1%] and 102 female [45.9%]) in 210 patients with an average age of 14.9 years (range, 9-18 years), met the inclusion criteria. Twenty-four patients (10.8%) underwent early surgery. All others were initially treated nonoperatively. Of the 198 patients in this group, 76 (38.4%) had recurrent instability, and 39 (51.3%) of these required surgical treatment. Recurrent instability was associated with trochlear dysplasia (P < .01). Patients with both immature physes and trochlear dysplasia had a recurrence rate of 69% (33/48), with a hazard ratio of 3.3. Age, sex, body mass index, and patella alta were not statistically associated with recurrent instability. Conclusion: Nonoperative treatment for first-time patellofemoral dislocation resulted in a 62% success rate. However, skeletally immature patients with trochlear dysplasia had only a 31% success rate with nonoperative management. Nearly half of patients with recurrent instability required surgical intervention to gain stability.

Medial Patellofemoral Ligament Repair for Recurrent Patellar Dislocation

Background The medial patellofemoral ligament (MPFL) is the primary restraint to extreme lateral displacement and is typically disrupted with an acute lateral patellar dislocation. Patients who fail a comprehensive nonoperative program and experience recurrent lateral patellar instability episodes are candidates for surgical treatment. Current surgical procedures include a variety of proximal realignment techniques, including repair or reconstruction of the MPFL along with distal realignment of the tibial tubercle when indicated. Purpose The objective of this study was to review the clinical, functional, and radiographic outcomes of isolated MPFL repair for recurrent lateral patellar dislocation. Study Design Case series; Level of evidence, 4. Methods The records of all patients undergoing MPFL repair for recurrent patellar dislocation at the Mayo Clinic from 2001 to 2006 were retrospectively reviewed. Twenty-seven patients (29 knees) with an average age of 19 years (range, 11-32 years) were included in this study. Clinical, functional, and radiographic outcomes were assessed at an average of 4 years after surgery (range, 2-7 years), using recurrent instability as the primary end point. Results The success rate of MPFL repair for preventing recurrent dislocations was 72% (21 of 29 knees). Eight patients (28%) experienced a recurrent lateral patellar dislocation. Five of these patients required a reoperation, including two MPFL reconstructions, 1 tibial tubercle osteotomy with MPFL reconstruction, 1 tibial tubercle osteotomy with revision MPFL repair, and 1 revision MPFL repair. At final follow-up, the mean Lysholm and Kujala scores were 86 (range, 42-100) and 92 (range, 57-105), respectively. Postoperative radiographs revealed a mean patellofemoral congruence angle improvement of 27° (range, 5°-44°). The only statistically significant risk factor for failure was nonanatomical MPFL repair at the medial femoral condyle (P = .004). Conclusion Isolated repair of the MPFL for recurrent patellar instability is associated with a relatively high failure rate, but remains a viable surgical option if surgical technique principles are followed. The clinical success of this operation depends on restoration of the anatomical origin of the MPFL and careful patient selection.

Wound complications after open Achilles tendon repair: an analysis of risk factors.

Operative treatment of Achilles tendon ruptures has the risk of wound complications. The purpose of this study is to determine the risk ratio for specific risk factors associated with wound related complications in patients with operatively treated Achilles tendon ruptures. Between 1978 and 2001, 167 open Achilles tendon repairs were done at our institution. Clinical data were retrospectively reviewed. Tobacco use, diabetes, age, gender, timing of surgery, body mass index and steroid use were evaluated as potential risk factors for wound healing complications. One patient was lost to follow-up and two patients had nonsimultaneous ruptures and only the first repair was included; the remaining patients were followed up until complete wound healing. There were 17 wound complications in 164 patients (10.4%). Significant risk factors for development of wound complications included tobacco use (p < 0.0001), steroid use (p = 0.0005), and female sex (p = 0.0400). For those patients who had one or more of the following risk factors: diabetes, tobacco use, or steroid use; eight of 19 (42.1%) had a complication, compared with nine of 145 (6.2%) for those without risk factors present (p < 0.0001). Surgeons doing open Achilles tendon repairs should be cognizant of the specific risk factors identified in this study, because they might impact decision making with regard to operative versus nonoperative treatment.

Effect of Graft Choice on the Outcome of Revision Anterior Cruciate Ligament Reconstruction in the Multicenter ACL Revision Study (MARS) Cohort

Background: Most surgeons believe that graft choice for anterior cruciate ligament (ACL) reconstruction is an important factor related to outcome; however, graft choice for revision may be limited due to previously used grafts. Hypotheses: Autograft use would result in increased sports function, increased activity level, and decreased osteoarthritis symptoms (as measured by validated patient-reported outcome instruments). Autograft use would result in decreased graft failure and reoperation rate 2 years after revision ACL reconstruction. Study Design: Cohort study; Level of evidence, 2. Methods: Patients undergoing revision ACL reconstruction were identified and prospectively enrolled by 83 surgeons at 52 sites. Data collected included baseline demographics, surgical technique, pathologic abnormalities, and the results of a series of validated, patient-reported outcome instruments (International Knee Documentation Committee [IKDC], Knee injury and Osteoarthritis Outcome Score [KOOS], Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC], and Marx activity rating score). Patients were followed up at 2 years and asked to complete the identical set of outcome instruments. Incidences of additional surgery and reoperation due to graft failure were also recorded. Multivariate regression models were used to determine the predictors (risk factors) of IKDC, KOOS, WOMAC, Marx scores, graft rerupture, and reoperation rate at 2 years after revision surgery. Results: A total of 1205 patients (697 [58%] males) were enrolled. The median age was 26 years. In 88% of patients, this was their first revision, and 341 patients (28%) were undergoing revision by the surgeon who had performed the previous reconstruction. The median time since last ACL reconstruction was 3.4 years. Revision using an autograft was performed in 583 patients (48%), allograft was used in 590 (49%), and both types were used in 32 (3%). Questionnaire follow-up was obtained for 989 subjects (82%), while telephone follow-up was obtained for 1112 (92%). The IKDC, KOOS, and WOMAC scores (with the exception of the WOMAC stiffness subscale) all significantly improved at 2-year follow-up (P < .001). In contrast, the 2-year Marx activity score demonstrated a significant decrease from the initial score at enrollment (P < .001). Graft choice proved to be a significant predictor of 2-year IKDC scores (P = .017). Specifically, the use of an autograft for revision reconstruction predicted improved score on the IKDC (P = .045; odds ratio [OR] = 1.31; 95% CI, 1.01-1.70). The use of an autograft predicted an improved score on the KOOS sports and recreation subscale (P = .037; OR = 1.33; 95% CI, 1.02-1.73). Use of an autograft also predicted improved scores on the KOOS quality of life subscale (P = .031; OR = 1.33; 95% CI, 1.03-1.73). For the KOOS symptoms and KOOS activities of daily living subscales, graft choice did not predict outcome score. Graft choice was a significant predictor of 2-year Marx activity level scores (P = .012). Graft rerupture was reported in 37 of 1112 patients (3.3%) by their 2-year follow-up: 24 allografts, 12 autografts, and 1 allograft and autograft. Use of an autograft for revision resulted in patients being 2.78 times less likely to sustain a subsequent graft rupture compared with allograft (P = .047; 95% CI, 1.01-7.69). Conclusion: Improved sports function and patient-reported outcome measures are obtained when an autograft is used. Additionally, use of an autograft shows a decreased risk in graft rerupture at 2-year follow-up. No differences were noted in rerupture or patient-reported outcomes between soft tissue and bone–patellar tendon–bone grafts. Surgeon education regarding the findings of this study has the potential to improve the results of revision ACL reconstruction.

CT and MRI Measurements of Tibial Tubercle–Trochlear Groove Distances Are Not Equivalent in Patients With Patellar Instability

Background: Tibial tubercle–trochlear groove distance (TT-TG) is a commonly used measurement for surgical decision making in patients with patellofemoral malalignment and instability. This measurement has historically been performed utilizing axial computed tomography (CT). More recently, magnetic resonance imaging (MRI) has been proposed as an equivalent method, but this has not yet been fully validated. Purpose: To determine the reliability of TT-TG distance measurements on both MRI and CT and to determine whether the measurements are interchangeable with one another. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: All patients with patellar instability who underwent both CT and MRI of the knee from 2003 to 2011 were included (n = 59 knees in 54 patients). Two fellowship-trained musculoskeletal radiologists measured the TT-TG distances for each patient by CT and MRI in a randomized, blinded fashion. Interobserver reliability was calculated between radiologists for both imaging modalities, and intermethod reliability was calculated between the 2 imaging modalities. The results are reported using intraclass correlation coefficients (ICCs) and Bland-Altman analysis. Results: The 59 knees had a mean TT-TG distance of 16.9 mm (range, 8.3-25.8 mm) by CT and 14.7 mm (range, 1.5-25.1 mm) by MRI. Interobserver reliability between the radiologists was considered excellent for both CT and MRI (ICC = 0.777 and 0.843, respectively). When comparing CT to MRI, the ICC was considered only fair for each of the raters (0.532 and 0.539). Eleven patients (19%) had a TT-TG distance of ≥20 mm on CT preoperatively and underwent distal realignment by tibial tubercle osteotomy. In this surgical subgroup, the mean TT-TG distance was 22.5 mm (range, 19.8-25.8 mm) by CT and only 18.7 mm (range, 14.4-22.8 mm) by MRI for a mean difference of 3.80 mm (P < .001). Conclusion: The TT-TG distance can be measured with excellent interrater reliability on both MRI and CT; however, the values derived from these 2 tests may not be interchangeable. This observation should be taken into consideration when MRI is used for surgical planning because MRI may underestimate the TT-TG distance when compared with CT.