Lateral Distance From the Osteotomy Hinge Point to the Tibial Cortex Is Associated With Lateral Hinge Fracture Type and Fracture Occurrence Time After Medial Open-Wedge High Tibial Osteotomy.

PURPOSE: To verify whether the distance from the hinge point to the tibial cortex affects the occurrence time and characteristics of the lateral hinge fracture (LHF) in medial open-wedge high tibial osteotomy. METHODS: We retrospectively reviewed 171 knees in 171 patients (121 women, 50 men; mean age, 53.9 years; range, 36-67 years) who had undergone medial open-wedge high tibial osteotomy with locking plate fixation between January 2011 and December 2020. Osteotomy hinge point and LHFs were identified on intraoperative fluoroscopy and immediate postoperative radiographs. LHF type was classified as suggested by Takeuchi et al. Acute fracture was defined as a fracture that occurred during surgery, and delayed fracture was defined as a fracture observed after 1 month postoperatively. The nearest distances from osteotomy hinge point to lateral, distal, and proximal cortex were measured on postoperative radiographs. We compared the distance between the different types and between acute and delayed LHFs. RESULTS: There were 55 LHFs (32%) (type I, 40 knees; type II, 14 knees; type III, 1 knee) that occurred acutely in 41 knees and were found as delayed fractures in 14 knees. The patient demographics were not significantly different between non-LHFs and each type of LHFs. Proximal and distal distances were not statistically different among fracture types and between occurrence times. However, lateral distances were significantly shorter in type I LHFs (6.2 ± 1.8 mm) and longer in type II LHFs (9.3 ± 2.3 mm) than in non-LHFs (7.1 ± 2.7 mm) (P = .020 and .004, respectively). The lateral cortical distances were also different between acute LHFs (6.4 ± 1.9 mm) and delayed LHF (9.0 ± 2.7 mm) (P < .001). In the case of fracture type, the frequency of type I decreases with increase in the lateral distance, whereas that of type II increases with increase in the lateral cortical distance. In acute fracture, type I was dominant (85.4%), whereas in delayed fracture, type II was dominant (57.2%). CONCLUSIONS: The lateral cortical distance from the hinge point was significantly associated with LHF occurrence. Shorter distance increased the risk for acute type I LHF, whereas longer distance increased the risk for delayed type II LHFs. LEVEL OF EVIDENCE: Level III, retrospective comparative prognostic trial.

Lateral Meniscal Allograft Transplantation Shows a Long-Term Chondroprotective Effect on Quantitative MRI T2 Mapping at 7 Years' Minimum Follow-Up.

PURPOSE: The purpose of this study was to assess the long-term chondroprotective effect of lateral meniscal allograft transplantation (MAT) using quantitative magnetic resonance imaging (MRI) T2 mapping. METHODS: In patients who underwent isolated lateral MAT, quantitative MRI T2 mapping was conducted preoperatively and postoperatively with at minimum follow-up of 7 years to assess the articular cartilage status. On the sagittal section image bisecting the lateral femoral condyle, the weight-bearing portions of the femoral and tibial articular cartilage were divided into 3 segments each-6 segments in total-based on the meniscal coverage area. The regions of interest analysis were performed on the 6 segments to measure the mean T2 value. Then, the whole layer was divided into deep and superficial layers for further zonal analysis. The longitudinal change in T2 values was statistically analyzed using paired t-tests. Clinical outcome was evaluated using the Lysholm score. RESULTS: A total of 31 patients were included in the study, with the MRI follow-up period of a minimum follow-up of 7 years (mean: 8.9 ± 1.3 years; range: 7.0-11.2 years). The mean T2 value of the whole layer showed significant improvement in all segments of the femoral cartilage and the posterior segment of tibial cartilage. In the zonal analysis, the mean T2 value of the tibial cartilage showed significant improvement in the superficial layer of the mid to posterior portion, while the deep layer remained stable. In contrast, the mean T2 value of the femoral cartilage showed significant improvement in the superficial and deep layers in all segments. The mean Lysholm score significantly improved from 62.6 ± 12.8 to 90.9 ± 10.5 (P < .001). CONCLUSION: This study suggests that MAT appears to have a long-term chondroprotective effect on the articular cartilage as judged by quantitative T2 mapping. LEVEL OF EVIDENCE: Level Ⅳ, case series.

Tear patterns and locations are different between lateral and medial compartments in patients with early anatomical failure after meniscal allograft transplantation.

PURPOSE: To investigate the characteristics of anatomically failed grafts within 1 year after meniscal allograft transplantation (MAT) and compare the differences between lateral and medial MATs. METHODS: The records of consecutive patients with anatomically failed grafts within 1 year after primary MAT between 2005 and 2018 were reviewed. Anatomical failure was defined as a tear covering > 50% of the allograft or an unstable peripheral rim. The pattern and location of the graft tears were analyzed using magnetic resonance imaging or arthroscopy. RESULTS: A total of 21 patients were included. All 21 patients had anatomical failure with tears involving > 50% of the allograft, whereas 15 had an unstable peripheral rim of the allograft. The mean failure time was 6.6 ± 3.6 months in all patients (lateral MAT, n = 15; medial MAT, n = 6). In the lateral MAT group, meniscocapsular separation was the most common pattern (n = 10, 66.7%), followed by complex (n = 3, 20.0%), radial (n = 1, 6.7%), and longitudinal (n = 1, 6.7%) tear. In the medial MAT group, a root tear was the most common pattern (n = 5, 83.3%), followed by a complex tear (n = 1, 16.7%). Meanwhile, in the lateral MAT, the midbody was the most frequently affected location (n = 9, 60.0%), followed by the posterior (n = 5, 33.3%) and anterior (n = 1, 6.7%) areas; in the medial MAT group, the posterior (n = 5, 83.3%) was the most frequently affected location, followed by the anterior area (n = 1, 16.7%). Significant differences in the pattern (P = 0.002) and location (P = 0.043) of the graft tears were found between lateral and medial MATs. CONCLUSION: In patients with early failure after MAT, meniscocapsular separation in the midbody of the lateral compartment and root tears in the posterior area of the medial compartment were the most common. Thus, surgeons are encouraged to pay extra attention to these vulnerable areas during the early period after MAT. LEVEL OF EVIDENCE: IV.

Nonextruded Grafts Result in Better Cartilage Quality After Lateral Meniscal Allograft Transplantation: Quantitative 3-T MRI T2 Mapping.

BACKGROUND: Several studies have reported that graft extrusion after meniscal allograft transplantation (MAT) is associated with deterioration of surgical outcomes. However, no study has investigated the effect of graft extrusion on the articular cartilage using objective quantitative methods. PURPOSE/HYPOTHESIS: This study aimed to investigate the influence of graft extrusion on the chondroprotective effect of lateral MAT on knee articular cartilage. We hypothesized that MAT without graft extrusion would result in better cartilage quality than MAT with graft extrusion. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Altogether, 105 patients who underwent isolated lateral MAT were divided into the extrusion and nonextrusion groups based on postoperative 3-month magnetic resonance imaging. Quantitative T2 mapping was performed on pre- and postoperative magnetic resonance imaging at midterm follow-up (mean ± SD, 3.2 ± 0.7 years). The weightbearing area of the femoral and tibial plateau articular cartilage was divided into 6 segments (F1, F2, F3, TP1, TP2, and TP3) from the anterior to posterior direction according to the meniscal coverage area. Each segment was further segmented into superficial and deep layers for zonal analysis. Longitudinal change in cartilage T2 value was compared between the groups. Lysholm scores were used to evaluate clinical function. RESULTS: The mean T2 value of the nonextrusion group showed a significant improvement in 14 of 18 segments after lateral MAT, whereas the extrusion group demonstrated no statistically significant change. The biochemical properties of cartilage tissue as judged by quantitative T2 mapping indicated improvement in the nonextrusion group as compared with the extrusion group in the F2, TP2, and TP3 segments overall; the deep layers of the F1, F2, and TP2 segments; and the superficial layer of the TP3 segment (P < .05). CONCLUSION: This study shows that the nonextruded graft results in better cartilage properties of the knee joint after lateral MAT as compared with the extruded graft at midterm follow-up.

Lateral Meniscal Allograft Transplantation Provides a Chondroprotective Effect on Articular Cartilage: Quantitative 3-T Magnetic Resonance Imaging T2 Mapping.

PURPOSE: This study aimed to assess the cartilage status in patients who underwent isolated lateral meniscus allograft transplantation (MAT) using preoperative and postoperative quantitative 3-T magnetic resonance imaging T2 mapping at midterm follow-up period. METHODS: Patients who underwent lateral MAT without cartilage treatment procedures between 2010 and 2019 were assessed by quantitative magnetic resonance imaging preoperatively and postoperatively. On the sagittal section image following the center of the lateral femoral condyle, the weight-bearing area of the articular cartilage was divided into 6 segments based on the meniscal coverage area from anterior to posterior direction. The mean T2 values of each of the 6 segments were measured for 3 regions of interest: overall, deep, and superficial layers. The change in T2 values was statistically analyzed by paired t-tests. The Lysholm score was used to evaluate clinical function. RESULTS: A total of 105 patients were included in the study. The mean follow-up period was 3.2 years (range 2.0-5.4 years). Among the 6 segments, the mean T2 value showed significant improvement in the overall layer of F2 (the middle weight-bearing area of femoral condyle) and TP3 (the posterior weight-bearing area of tibia condyle) segments (P = .013 and .021, respectively) and the superficial layer of the F3 (the posterior weight-bearing area of femoral condyle) segments (P = .028). The mean T2 value of all the other segments did not show a statistically significant change. The mean Lysholm score significantly improved from 66.5 ± 15.8 to 89.3 ± 10.0 (P < .001). Overall, 73.3% and 96.2% of the patients met the minimal clinically important difference and patient acceptable symptomatic state, respectively. CONCLUSIONS: The mean T2 value of the articular cartilage of the weight-bearing area was either maintained or showed statistically significant improvement depending on the location following isolated lateral MAT. Thus, the transplanted meniscus seems to have a chondroprotective effect on the weight-bearing cartilage. LEVEL OF EVIDENCE: Level IV, retrospective therapeutic case series.

Effect of ICRS Lesion Grade on Graft Survival After Medial Meniscal Allograft Transplantation: MRI-Based Objective Evaluation.

BACKGROUND: Data are lacking regarding the survival rate after medial meniscal allograft transplantation (MAT) alone. Furthermore, little information is available about prognostic factors for graft survival that affect the outcomes of medial MAT. PURPOSE: To investigate the prognostic factors and survival rate of allograft after medial MAT. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: The records of 78 consecutive patients who underwent primary medial MAT between 1996 and 2018 were reviewed. Kaplan-Meier survival analysis was performed to analyze the anatomic and clinical survival rates. Anatomic failure was defined as a tear covering >50% of the allograft or unstable peripheral rim. Clinical failure was considered Lysholm score <65 or need for additional surgery such as meniscal repair, revision MAT, realignment osteotomy, and meniscectomy for >50% of the allograft. Patient factors affecting anatomic and clinical failure were analyzed. RESULTS: The mean follow-up period was 6.9 ± 5.3 years (range, 2-21 years). Anatomic failure was noted in 19 patients (24.4%), and none of these patients had a persistent poor Lysholm score of <65; of these, 2 patients who underwent meniscal repair also had clinical failure. Clinical failure was noted in 7 patients (9.0%); 4 patients had Lysholm score <65, 2 patients underwent meniscal repair, and 1 patient underwent realignment osteotomy. The estimated 10-year anatomic and clinical survival rates were 73.89% and 87.90%, respectively. Anatomic survival was significantly associated with only high-grade International Cartilage Regeneration & Joint Preservation (ICRS) lesion (ICRS grade 3 or 4) (hazard ratio, 3.171; 95% CI, 1.124-8.944; P = .029). However, the clinical survival rate was not significantly associated with any factors. Patients with low-grade ICRS lesion (ICRS grade 0, 1, or 2) showed a higher estimated 10-year anatomic survival rate compared with patients with high-grade ICRS lesions (87.6% vs 63.3%, respectively; P = .022). CONCLUSION: Low-grade ICRS lesion was associated with higher anatomic survival rate after medial MAT. In patients with high-grade ICRS lesions, the clinical outcome might be good; however, the status of an allograft might be poor. The surgeon should be aware of this and explain to the patient that close observation is necessary.

Periimplant osteolysis does not affect the outcome of rotator cuff repair: a systematic review and meta-analysis.

PURPOSE: The goal of this study was to perform a systematic review and meta-analysis to compare the clinical and radiologic outcomes of rotator cuff repair, depending on the presence of developed periimplant osteolysis (PIO) after using suture anchors. METHODS: The electronic databases of MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were searched for articles published up until October 2019 to find relevant articles comparing the outcomes of rotator cuff repair between the periimplant osteolysis group and non-periimplant osteolysis group. Data searching, extraction, analysis, and quality assessment were performed according to the Cochrane Collaboration guidelines. The results are presented as risk ratio (RR) for binary outcomes and standardised mean difference (SMD) for continuous outcomes with 95% confidence intervals (CI). RESULTS: Six clinical studies were included. No significant differences were found between the group with periimplant osteolysis and the group without periimplant osteolysis regarding retear rate (RR = 1.34; 95% CI 0.93-1.94; I2 = 28%), postoperative clinical scores (SMD = 0.29; 95% CI - 0.26 to 0.83; I2 = 80%) and range of motion (ROM); forward flexion (SMD = 0.39; 95% CI - 0.16 to 0.93; I2 = 0%), external rotation (SMD = - 0.10; 95% CI - 0.64 to 0.45; I2 = 0%) and internal rotation (SMD = - 0.37; 95% CI - 0.92 to 0.17; I2 = 0%). CONCLUSION: The presence of periimplant osteolysis after rotator cuff repair with suture anchor does not affect the clinical outcomes such as retear rate, clinical scoring, and ROM. However, as there was no standard consensus on the criteria for evaluating periimplant osteolysis, this result may not fully reflect the effect of periimplant osteolysis depending on its severity. LEVEL OF EVIDENCE: Level IV.

Arthroscopic treatment for intratendinous rotator cuff tear results in satisfactory clinical outcomes and structural integrity.

PURPOSE: This study aimed to evaluate the clinical outcomes and structural integrity of arthroscopic repair of intratendinous rotator cuff tear. METHODS: Patients who were diagnosed with an intratendinous tear but in whom conservative treatment failed were selected and underwent arthroscopic repair. Between 2008 and 2014, a total of 30 patients (6 men, 24 women; mean age, 59 ± 3.7 years) met the inclusion criteria and were followed up. The mean follow-up period was 26.3 ± 0.7 months. The results were evaluated using the University of California at Los Angeles (UCLA) score, the Society of the American Shoulder and Elbow Surgeons rating scale (ASES) questionnaire, and the visual analog scale (VAS) and range of motion (ROM) were measured preoperatively and at final follow-up. Magnetic resonance imaging (MRI) was performed preoperatively and at 6.7 ± 0.2 months postoperatively. Postoperative MRI was performed on 27 out of 30 patients and analysed using the Sugaya classification. RESULTS: Corresponding to the preoperative MRI findings, arthroscopic findings of intratendinous tears were observed in all 30 patients. The mean active forward elevation ROM was 137.3° ± 15.4° before surgery and 168.8° ± 15.2° at the final follow-up. The internal and external rotations at abduction were 31.7° ± 5.1° and 63.0° ± 11.6° before surgery, respectively, and 60.5° ± 8.0° and 75.2° ± 10.8° after surgery, respectively. The UCLA score improved from of 20.1 ± 7.4 points preoperative to 28.4 ± 5.5 points at the final follow-up. The ASES score improved from 55.7 ± 15.3 points preoperative to 82.6 ± 9.7 points postoperatively. The VAS for pain score decreased from 6.4 ± 1.2 points preoperative to 1.6 ± 0.9 points postoperative. Satisfactory outcomes (excellent/good) in terms of UCLA and ASES scores were observed in 29 of 30 patients. Based on Sugaya classification, grades I, II, and III structural integrities were observed in 9, 14, and 4 patients, respectively. CONCLUSIONS: Successful clinical outcomes and structural integrity can be achieved with arthroscopic repair of intratendinous rotator cuff tears involving more than half thickness (> 50%). Therefore, arthroscopic repair is a practical next treatment option for patients with intratendinous rotator cuff tears in whom conservative treatment fails. LEVEL OF EVIDENCE: IV.

Differences between the Upper Extremity and the Lower Extremity in Reconstruction Using an Anterolateral Thigh Perforator Flap.

BACKGROUND: While reconstruction of soft tissue defects is the common purpose, surgical reconstructions of upper extremities and lower extremities have different goals in terms of functional and aesthetic outcomes. The purpose of the current study was to compare and analyze differences between reconstructions of upper extremities and lower extremities using an anterolateral thigh (ALT) flap. METHODS: We analyzed 74 patients who underwent reconstructions of upper extremities and lower extremities using an ALT flap from October 2006 to August 2012 (upper extremities, 45 cases; lower extremities, 29 cases). The study focused on the statistical analysis of patient satisfaction according to the donor site of the ALT flap and the timing of a debulking procedure. RESULTS: On the choice of donor site, in the upper extremity reconstruction, flap elevation from the opposite side of the recipient limb was preferred (p = 0.019) because it causes less inconvenience while walking. In the lower extremity reconstruction, flap elevation from the same side of the recipient limb (p = 0.002) was preferred. The debulking procedure performed on the upper extremities at 4 weeks after reconstruction led to better functional results and enhanced patient satisfaction (p = 0.022). In the case of lower extremities, enhanced satisfaction was noted in patients who underwent the procedure at 6 months after reconstruction (p < 0.001). CONCLUSIONS: Elevation of the flap in reconstruction reduced inconvenience when performed on the same side of the recipient limb for lower extremities and on the opposite side for upper extremities. In addition, debulking resulted in better satisfaction when performed 4 weeks postoperatively in the upper extremities and 6 months postoperatively in the lower extremities.