Nobuyuki Kumahashi

A Minimum 2-Year Follow-up After Selective Anteromedial or Posterolateral Bundle Anterior Cruciate Ligament Reconstruction

PURPOSE The purpose of this study was to investigate the 2-year follow-up clinical results of 45 patients who had undergone our anterior cruciate ligament (ACL) augmentation procedure using an autogenous semitendinosus tendon and the EndoButton CL (Smith & Nephew, Andover, MA). METHODS We followed up 45 patients for more than 2 years after their ACL augmentations. Of these, 37 were anteromedial (AM) bundle reconstructions and 8 were posterolateral (PL) bundle reconstructions. They were assessed using a KT-2000 knee arthrometer (MEDmetric, San Diego, CA) at 30 lb by joint position sense, Lysholm knee score, and magnetic resonance imaging (MRI). RESULTS The mean side-to-side difference of anterior displacement measured by the KT-2000 knee arthrometer at 30 degrees of knee flexion preoperatively was 3.3 +/- 2.4 mm, significantly improving to a mean of 0.5 +/- 2.7 mm 2 years after surgery. The preoperative joint position sense inaccuracy was 1.6 degrees +/- 1.8 degrees , which improved significantly to 0.3 degrees +/- 2.0 degrees after surgery. The median Lysholm knee score significantly improved from 74 (range, 44 to 95) to 100 points (range, 81 to 100) after surgery. In 20 of 29 patients who had the postoperative MRI examination, the augmented ACL resembled 1 bundle on the sagittal planes of the postoperative MRI. CONCLUSIONS Selective AM or PL bundle reconstruction showed improved joint stability, joint position sense, and Lysholm scores postoperatively. This procedure can be a treatment option for patients whose ACL remnants are left in certain conditions.

Arthroscopic Drilling With Debridement of Remaining Cartilage for Osteochondral Lesions of the Talar Dome in Unstable Ankles

Background Arthroscopic examination has shown that the regenerative cartilage that appears after arthroscopic drilling for thetreatment of osteochondral lesions of the talar dome does not always cover the cartilage defect sufficiently. Hypothesis The remaining degenerative cartilage at the lesions may obstruct the healing of the articular cartilage. Study Design Prospective cohort study. Methods Thirty-nine patients underwent arthroscopic drilling that kept the remaining cartilage at the lesion (group A), and 30patients underwent arthroscopic drilling that removed the remaining cartilage at the lesion (group B). At 1 year after theoperation, we performed ankle arthroscopy to evaluate the cartilage condition. Results The arthroscopic findings revealed that in group A, 11 cases (28.2%) were improved, 12 cases (30.8%) wereunchanged, and 16 cases (41.0%) had deteriorated; in group B, 27 cases (93.1%) were improved and 2 cases were unchanged. There were significant differences between group A and group B in the rate of cases whose cartilage condition was seen toimprove under arthroscopic examination (P< 0.0001). Conclusions The study shows that in the treatment of osteochondral lesions of the talar dome, the removing of the remainingdegenerative cartilage may be of some benefit in the treatment of these lesions.

A “sandwich” method of reconstruction of the medial patellofemoral ligament using a titanium interference screw for patellar instability in skeletally immature patients

BackgroundNo standard surgical procedure for medial patellofemoral ligament (MPFL) reconstruction exists in skeletally immature patients with patellar instability. This study aimed to evaluate the clinical effectiveness of a novel reconstruction technique for the MPFL in patients with patellar instability because of non-closure of the epiphyseal line.MethodsThe “sandwich” method was fixation of the patella between a double-stranded semitendinosus tendon through the posterior third of the femoral insertion of the medial collateral ligament (MCL) as a pulley with a titanium interference screw in a single patellar tunnel. Five knees in five patients were studied: four with recurrent and one with habitual patellar dislocations. Subjects underwent MPFL reconstruction with or without lateral release. Patients were evaluated using pre-operative and post-operative physical and radiographic examinations, including apprehension testing, assessment of tilting and congruence angles, medial and lateral shift ratios under stress measured using X-ray imaging, and Kujala and Lysholm scores.ResultsNo patient experienced recurrent post-operative episodes of dislocation or subluxation. By the final follow-up, patellar apprehension had disappeared in all patients. In addition, all patients showed significant improvement in the following: tilting angle, congruence angle, lateral shift ratio, Kujala score, and Lysholm score.ConclusionsThe MPFL reconstruction methods, using a double-stranded semitendinosus autograft and sparing the femoral physeal line in non-closure of the epiphyseal line, provide acceptable short-term results for the treatment of patellar instability.

Correlation of changes in pain intensity with synovial fluid adenosine triphosphate levels after treatment of patients with osteoarthritis of the knee with high-molecular-weight hyaluronic acid.

We sought to determine whether a clinical association exists between osteoarthritis (OA)-associated knee pain and adenosine triphosphate (ATP) levels in synovial fluid (SF). A total of 28 patients with 28 primary OA knees were included. They routinely received intra-articular injection of high-molecular-weight hyaluronic acid (HA) once weekly for 5 weeks (treated group). Eight patients without knee pain who had undergone an operation for anterior or posterior cruciate ligament reconstruction 2 years ago were also examined (control group). SF and blood ATP concentrations, total amount of ATP, total SF volume, and Visual Analogue Scale (VAS) scores in all patients were measured and we compared pre-treatment values with those 1 week after the final treatment. We evaluated the correlation of change in total ATP (ΔATP) and change in VAS score (ΔVAS), ΔVAS and change in SF volume (ΔSF), and ATP concentration in SF and blood. In the treated group, SF ATP concentration, total amount of ATP, SF volume, and VAS score were all significantly lower post-treatment than pre-treatment (p = 0.0005, 0.0003, 0.0022, and < 0.0001, respectively). In treated group, ΔVAS was significantly associated with ΔATP (r = 0.56, p = 0.0032), ΔSF was significantly associated with ΔVAS (r = 0.78, p < 0.0001), and total amount of SF ATP and SF volume at pre-treatment were significantly higher than the control group (p < 0.0001, p < 0.0001) We demonstrated an association between SF ATP level changes and OA knee pain, which should facilitate a further understanding of OA pain mechanisms.

A longitudinal study of the quantitative evaluation of patella cartilage after total knee replacement by delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) and T2 mapping at 3.0 T: preliminary results

OBJECTIVE To characterize the quantitative changes of patella cartilage over time after total knee arthroplasty (TKA) by delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) and T2 mapping at 3.0 T. METHOD Twenty-six knees of 26 patients (23 women and three men, mean age, 75 years) with primary osteoarthritis and osteonecrosis of the knee underwent TKA with a zirconia ceramic implant in this prospective study. Twelve patients without patella resurfacing (NR group) and 14 patients with patella resurfacing (R group) had TKA with cemented fixation. The implant position was examined by radiograph, computed tomography (CT) and magnetic resonance imaging (MRI). The clinical scores were checked pre-operatively, 1 year post-operatively and at the final follow-up. Patella cartilage and its thickness were evaluated pre-operatively and 1 year after TKA by dGEMRIC and T2 mapping in the NR group only. Patella cartilage was divided into eight regions of interest: the deep and superficial layers of the outer lateral and medial half, and the inner lateral and medial half from the central ridge. RESULTS The implant position was appropriate in all cases and clinical scores were not significantly different between the two groups. The post-operative dGEMRIC value of the outer medial half superficial zone in the NR group was significantly decreased compared with the pre-operation value (P<0.05), whereas T2 mapping was not significantly changed in all zones. The cartilage thickness of the outer zone was significantly thinner post-operatively (P<0.05). CONCLUSIONS These findings indicate that osteoarthritic changes in the outer zone of patella cartilage occurred 1 year after TKA.

A comparison of patient-reported outcomes and arthroscopic findings between drilling and autologous osteochondral grafting for the treatment of articular cartilage defects combined with anterior cruciate ligament injury.

BACKGROUND To compare the patient-reported outcomes and arthroscopic findings between drilling and autologous osteochondral grafting (AOG) for the treatment of articular cartilage defects combined with anterior cruciate ligament (ACL) injuries. METHODS The subjects were 40 patients who had articular cartilage defects in the weight-bearing part of the medial and lateral femur condyle combined with ACL injuries that were treated by drilling (20 patients) or AOG (20 patients) at the same time as ACL reconstruction was performed. In the drilling group patients, lesions were penetrated with multiple 1.2-mm Kirschner wires, and in the AOG group patients, grafts were made to cartilage defects from one to three osteochondral pegs harvested from the less-weight-bearing periphery of the articular surface of the femoral condyle. The patient-reported outcomes were assessed using the International Knee Documentation Committee (IKDC) subjective knee examination score. Second-look arthroscopy was performed to evaluate the repaired cartilage macroscopically. RESULTS The median follow-up duration was 25 (range, 12-42) months. The IKDC scores were significantly improved from 64.4 to 95.4 points in the drilling group and from 52.3 to 94.3 points in the AOG group, with no difference between the two groups, although there was a difference in the repaired cartilage findings of arthroscopy. CONCLUSION In this study, no differences in IKDC scores were found in patients with a concomitant ACL rupture and an osteochondral lesion treated by drilling or AOG at a minimum follow-up of 1year, regardless of the differences at arthroscopic grading of the ICRS classification. LEVEL OF EVIDENCE Case-control study (LEVEL III).

Clinical Outcomes of Revision Meniscal Repair A Case Series

Background: Meniscal preservation results in better clinical outcomes than meniscectomy; however, no studies have evaluated the results of revision meniscal repair. Hypothesis: Revision meniscal repair can achieve good clinical outcomes. Study Design: Case series; Level of evidence, 4. Methods: The study participants were 16 patients with symptomatic meniscal retears of a total of 96 patients who underwent primary arthroscopic meniscal repair. Fifteen of these 16 patients underwent revision meniscal repair. The mean age at revision was 27 years, and the mean duration between the primary operation and revision was 27 months. Eight patients had degenerative changes of the meniscus at revision. Clinical outcomes were assessed using the Lysholm score and the Tegner sports activity score, and image assessment was performed using magnetic resonance imaging. Results: Five patients had re-retears of a resutured meniscus, and the mean duration between revision and the re-retear was 25 months (range, 8-68 months). The mean follow-up of patients without re-retears was 41 months (range, 24-74 months), and the mean Lysholm score in those without re-retears significantly improved from 81.4 points (range, 73-89 points) at pre-revision to 97.4 points (range, 90-100 points) at the final survey (P = .0001). Degenerative changes of the meniscus at the revision site were observed in all 5 patients with re-retears but in only 3 of the 10 patients without re-retears. Conclusion: Revision meniscal repair should be considered in the setting of a retorn meniscus without degenerative changes.

Effectiveness and biocompatibility of a novel biological adhesive application for repair of meniscal tear on the avascular zone

Abstract We have investigated the effectiveness and safety of a newly developed biological adhesive for repair of meniscal tear. The adhesive was composed of disuccinimidyl tartrate (DST) as a crosslinker and human serum albumin (HSA) as a hardener. To determine adequate concentration, bonding strength was measured using a tensiometer 5 min after applying the adhesive on the avascular zone tear of porcine meniscus; it was compared with the strengths of commercially available cyanoacrylate-based and fibrin-based adhesives. In vivo examination was performed using Japanese white rabbits, creating longitudinal tears on the avascular zone of meniscus and applying DST–HSA adhesive. Three months after operation the rabbits were sacrificed and tension test and histological evaluation were performed. Bonding strength was measured in three porcine meniscus groups: (i) only suturing, (ii) suturing after applying the adhesive on surface and (iii) suturing using an adhesive-soaked suture. The optimum concentrations were 0.1 mmol of DST and 42 w/v% of HAS. Bonding strength was greatest with cyanoacrylate-based adhesive, followed by DST–HSA adhesive, and fibrin-based adhesive. No inflammation was observed in the synovium or surrounding tissues 3 months after using the DST–HSA adhesive. Bonding strength was greatest with DST–HSA adhesive-soaked suturing group (77 ± 6 N), followed by suturing only group (61 ± 5 N) and surface adhesive application group (60 ± 8 N). The newly developed DST-HSA adhesive is considered safe and may be effective in enforcement of bonding of avascular zone tear of the meniscus.

Longitudinal Change of Medial and Lateral Patellar Stiffness After Reconstruction of the Medial Patellofemoral Ligament for Patients with Recurrent Patellar Dislocation.

BACKGROUND Longitudinal changes in patellar stiffness following reconstruction of the medial patellofemoral ligament for recurrent patellar dislocation at full extension are unknown. METHODS Fifteen consecutive patients (three men and twelve women, with a mean age of twenty-two years) with seventeen knees were matched by sex and age to thirty-two reference subjects in this prospective study. The follow-up period was a minimum of twenty-four months. The medial patellofemoral ligament reconstruction used an autograft semitendinosus tendon and an interference screw system with or without lateral release under 10 N of laterally directed force. The medial patellar stiffness and lateral patellar stiffness were measured in 0° of knee extension using the Patella Stability Tester preoperatively; postoperatively at three, six, twelve, and eighteen months; and at the time of the latest follow-up. Before and after the surgical procedure, patients were evaluated for apprehension and Kujala and Lysholm scores; radiographic examinations were performed to evaluate changes, including osteoarthritic changes. RESULTS The medial stiffness of the affected side before the surgical procedure was significantly lower than the lateral stiffness (p = 0.004) and the stiffness for healthy reference knees (p = 0.004). Medial stiffness three months after the surgical procedure was significantly elevated compared with lateral values (p = 0.027), preoperative values (p < 0.001), and reference group values (p = 0.002); reached the reference level by six months; and was maintained for up to two years. Furthermore, medial stiffness and lateral stiffness were well balanced after six months and this balance was sustained for up to two years postoperatively. No recurrent dislocation occurred during the follow-up period; one patient experienced apprehension. Postoperative radiographic findings and clinical scores were significantly improved at the time of the latest follow-up (p < 0.05). One knee progressed to patellofemoral osteoarthritis. CONCLUSIONS The value for medial stiffness was significantly improved three months after medial patellofemoral ligament reconstruction compared with the preoperative and lateral values and returned to the reference level by six months. Medial stiffness and lateral stiffness of the patella were well balanced by six months and retained that balance for up to two years, with good clinical results. LEVEL OF EVIDENCE Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Fixation of osteochondral fractures of the patella using autologous bone screws when reconstructing the medial patellofemoral ligament after recurrent patellar dislocation: report of two cases

Osteochondral fractures of the patella are commonly seen after its acute or recurrent dislocation. Without fixation of the osteochondral fragment, osteoarthritis can occur [1, 2]. Conventional methods for fixation of osteochondral fractures of the patella include metal screws [3, 4], bioabsorbable pins and screws [5], and bone pegs [6–8]. Bone screws for some clinical applications have been reported for osteosynthesis after mandibular correction osteotomy [9]. Mori et al. developed bone screws made of cortical bone for osteochondral fragment fixation which have osteointegrative properties and high mechanical strength comparable with that of conventional screws [10]; they ensure successful fixation because of precise and stable repair and biological healing [10, 11]. Kono et al. [12] reported better tissue repair of cartilage defects on fragments at the entrance to screw holes when osteochondral fractures were treated with bone screws rather than poly-Llactic acid (PLLA) screws. There have been no reports of precise clinical observations after use of bone screws to treat osteochondral fractures of the patella. The purpose of this study was to evaluate the use of this bone-screw technique to repair osteochondral fractures after recurrent patellar dislocation. Two cases of fixation of osteochondral fractures of the patella using autologous bone screws with medial patellofemoral ligament (MPFL) reconstruction are reported. Report of two cases