Kwang-Won Lee

The development and validation of an appraisal method for rotator cuff disorders: The Korean Shoulder Scoring System

HYPOTHESIS The purpose of this study was to develop and validate a disease-specific appraisal method for patients with rotator cuff disorders. The Korean Shoulder Scoring System (KSS) includes 5 domains totalling 100 points: function, 30 points; pain, 20; satisfaction, 10; range of motion, 20; and muscle power, consisting of strength, 10; and endurance, 10. METHOD The KSS was used to evaluate clinical outcomes of 430 patients with rotator cuff disorder for a period of 6 months postoperatively. RESULT The KSS had an acceptable level of internal consistency (alpha = 0.840). The KSS scores also correlated strongly with the Constant scores (r = 0.802), but less so with the American Shoulder and Elbow Surgeons scores (r = 0.602) and the University of California Los Angeles shoulder scores (r = 0.573). A large effect size (r = 1.234) and a standardized response mean (r = 1.317) for KSS were evident at 6 months postoperatively. CONCLUSION The KSS is a useful measurement tool that combines subjective and objective evaluations for shoulder function related to rotator cuff disorders.

Arthroscopy of the First Metatarsophalangeal Joint in 59 Consecutive Cases

The authors analyzed the results of 59 consecutive cases of the first metatarsophalangeal (MTP-I) joint arthroscopy to verify the efficacy and safety of the procedure. Fifty-nine patients were followed for >18 months after MTP-I joint arthroscopic procedures. The mean duration of follow-up was 25 months. Clinically, the American Orthopaedic Foot and Ankle Society (AOFAS) hallux metatarsophalangeal-interphalangeal scale and the satisfaction of the patients were evaluated. Hallux valgus angle, the first intermetatarsal angle, and medial sesamoid position were analyzed in cases of hallux valgus. The American Orthopaedic Foot and Ankle Society hallux metatarsophalangeal-interphalangeal scale score was increased from 69 points preoperatively to 92 points postoperatively (p < .05). Radiologically, the mean hallux valgus angle was decreased from 29.2° preoperatively to 9.7° postoperatively (p < .05). The mean first intermetatarsal angle was decreased from 14.8° preoperatively to 7.7° postoperatively (p < .05). The medial sesamoid position was improved from 4.8 preoperatively to 2.0 postoperatively (p < .05). Ninety-five percent of the patients were satisfied with the procedures. There was 1 case of a wound problem and 1 case of temporary digital nerve injury as complications. Based on our experience, arthroscopy of MTP-I joint appears to be a safe and reproducible procedure for selected cases of MTP-I joint disorders.

Clinical and Radiological Evaluation after Arthroscopic Rotator Cuff Repair Using Suture Bridge Technique

Background We retrospectively assessed the clinical outcomes and investigated risk factors influencing retear after arthroscopic suture bridge repair technique for rotator cuff tear through clinical assessment and magnetic resonance arthrography (MRA). Methods Between January 2008 and April 2011, sixty-two cases of full-thickness rotator cuff tear were treated with arthroscopic suture bridge repair technique and follow-up MRA were performed. The mean age was 56.1 years, and mean follow-up period was 27.4 months. Clinical and functional outcomes were assessed using range of motion, Korean shoulder score, Constant score, and UCLA score. Radiological outcome was evaluated with preoperative and follow-up MRA. Potential predictive factors that influenced cuff retear, such as age, gender, geometric patterns of tear, size of cuff tear, acromioplasty, fatty degeneration, atrophy of cuff muscle, retraction of supraspinatus, involved muscles of cuff and osteolysis around the suture anchor were evaluated. Results Thirty cases (48.4%) revealed retear on MRA. In univariable analysis, retear was significantly more frequent in over 60 years age group (62.5%) than under 60 years age group (39.5%; p = 0.043), and also in medium to large-sized tear than small-sized tear (p = 0.003). There was significant difference in geometric pattern of tear (p = 0.015). In multivariable analysis, only age (p = 0.036) and size of tear (p = 0.030) revealed a significant difference. The mean active range of motion for forward flexion, abduction, external rotation at the side and internal rotation at the side were significantly improved at follow-up (p < 0.05). The mean Korean shoulder score, Constant score, and UCLA score increased significantly at follow-up (p < 0.01). The range of motion, Korean shoulder score, Constant score, and UCLA score did not differ significantly between the groups with retear and intact repairs (p > 0.05). The locations of retear were insertion site in 10 cases (33.3%) and musculotendinous junction in 20 cases (66.7%; p = 0.006). Conclusions Suture bridge repair technique for rotator cuff tear showed improved clinical results. Cuff integrity after repair did not affect clinical results. Age of over 60 years and size of cuff tear larger than 1 cm were factors influencing rotator cuff retear after arthroscopic suture bridge repair technique.

Anatomic Single Bundle Anterior Cruciate Ligament Reconstruction by Low Accessory Anteromedial Portal Technique: An In Vivo 3D CT Study.

Purpose Proper femoral tunnel position is important for anatomical reconstruction of the anterior cruciate ligament (ACL). The purpose of this study was to evaluate the positions of femoral and tibial tunnels created using an accessory anteromedial portal technique in single bundle ACL reconstruction. Materials and Methods The femoral tunnel was targeted at the mid-portion of the ACL bundles. We evaluated postoperative computed tomography scans of 32 patients treated by ACL reconstruction using a free-hand low accessory anteromedial portal technique. On the tibial side, the tunnel position was evaluated using Tsukadas method. On the femoral side, the position was evaluated using 1) the quadrant method, 2) Mochizukis method, 3) Mochizukis method, and 4) Takahashis method. Tunnel obliquity was also evaluated. Results The mean tibial tunnel position was located at 44.6%±2.5% anterior from the anterior margin and 48.0%±3.0% in medial from the medial margin. The mean femoral tunnel position was located at the center between the anteromedial and posterolateral bundles: Quadrant method, 26.7%±2.7%/30.0%±2.9%; Watanabes method, 37.7%±2.5%/26.6%±2.2%; Mochizukis method, 38.7%±2.7%; Takahashis method, 21.8%±2.2%. The mean femoral tunnel obliquity was 57.7°±6.2° in the sagittal plane and 49.9°±5.6° in the coronal plane. Conclusions In anatomic single bundle ACL reconstruction, the low anteromedial portal technique can restore accurate position of the native footprint. Accurate femoral tunnel position facilitates recovery of stability and decreases graft failure rate.

Cemented versus cementless fixation of a tibial component in LCS mobile-bearing total knee arthroplasty performed by a single surgeon.

Although cemented tibial fixation of total knee arthroplasty accepted as the gold standard, cementless fixation as a means to supplement disadvantages of cemented fixation continues to be of interest to clinicians. One hundred sixty-eight consecutive knees undergoing primary knee arthroplasty for osteoarthritis were randomly assigned to receive either a cemented (86 knees) or cementless (82 knees) fixation of tibial component. We report the outcomes at 8 to 11years (mean, 9.5). The mean KSS, the HSS score, the mean WOMAC, the mean ranges of knee movement and radiological results were similar in both groups. No osteolysis was identified in either group. The rate of survival of the femoral and tibial components was 100% in both groups at final follow-up.

Investigation on radiation degradation of carboxymethylcellulose by ionizing irradiation.

This study was done to compare the effects of irradiations with gamma-rays and electron beams, on the viscosity of the carboxymethylcellulose (CMC), on the functional groups of CMC, and on the production of radicals. It was observed that the relative viscosities decreased as the irradiation doses increased, but the decrease was more significant when irradiation with gamma rays. FT-IR spectra showed no significant difference between the gamma-ray and the electron beam irradiated samples. ESR spectra showed that the gamma-ray irradiation produced more radicals than electron beam irradiation in CMC.

Effective healing of chronic rotator cuff injury using recombinant bone morphogenetic protein-2 coated dermal patch in vivo

Biologic augmentation for rotator cuff repair is a challenging treatment in patients with chronic large, massive, and irreparable rotator cuff injuries. Particularly, the use of an extracellular matrix (ECM) patch such as dermal tissue offered improved biomechanical properties in previous studies. Cytokines induce cell chemotaxis, proliferation, matrix synthesis, and cell differentiation. Moreover, osteoinductive growth factors such as bone morphogenetic protein-2 (BMP-2) affect the formation of new bone and fibrocartilage in lesions. However, the effects of using a dermal patch in combination with BMP-2 have not been evaluated to date, although many researchers have recognized the importance thereof. In this study, rhBMP-2-coated dermal patch (1 cm × 2 cm) isolated from human cadaveric donor was inserted in a rabbit model of chronic rotator cuff injury for in vivo evaluation. Bone mineral density and biomechanical strength were tested and histological and histomorphometric analyses were performed. The results showed that insertion of an rhBMP-2-coated acellular dermal patch not only significantly ameliorated new bone formation, it also improved biomechanical properties such as ultimate tensile strength. Thus, the use of this combination may improve the chronic rotator cuff injury-healing rate and clinical outcomes after rotator cuff repair.

A Comparison of Conventional Ultrasonography and Arthrosonography in the Assessment of Cuff Integrity after Rotator Cuff Repair

Background This study was designed to perform conventional ultrasonography, magnetic resonance arthrography (MRA) and arthrosonography exams after rotator cuff repair to compare the results of conventional ultrasonography and arthrosonography with those of MRA as the gold standard. Methods We prospectively studied 42 consecutive patients (14 males, 28 females; average age, 59.4 years) who received arthroscopic rotator cuff repair due to full-thickness tears of the supraspinatus tendon from 2008 to 2010. The integrity assessment of the repaired rotator cuff was performed 6 months postoperatively using conventional ultrasonography, MRA, and arthrosonography. Results The diagnostic accuracy of the conventional ultrasonography compared to MRA was 78.6% and the McNemar test results were 0.016 in full-thickness tear and 0.077 in partial-thickness tear. The diagnostic accuracy of arthrosonography compared to MRA was 92.9% and the McNemar test results were 0.998 in full-thickness tear and 0.875 in partial-thickness tear. Conclusions It was found that the integrity assessment of the repaired rotator cuff by ultrasonography must be guarded against and that arthrosonography is an effective alternative method in the postoperative integrity assessment. Also, an arthrosonography seems to be a suitable modality to replace the conventional ultrasonography.

Tendon–bone interface healing using an injectable rhBMP‐2‐containing collagen gel in a rabbit extra‐articular bone tunnel model

This study examines the hypothesis that injectable collagen gel can be an effective carrier for recombinant human bone morphogenetic protein‐2 (rhBMP‐2)’s localization to the healing tendon–bone interface. In 36 mature New Zealand White rabbits, the upper long digital extensor tendon was cut and inserted into the proximal tibial bone tunnel. Then a rhBMP‐2‐containing collagen gel was injected into the tendon–bone tunnel interface, using a syringe. Histological and biomechanical assessments of the tendon–bone interface were conducted at 3 and 6 weeks after implantation. In vitro testing showed that the semi‐viscous collagen gel at room temperature was transformed into a firm gel state at 37°C. The rhBMP‐2 release profile showed that rhBMP‐2 was released from the collagen gel for more than 28 days. In vivo testing showed that fibrocartilage and new bone are formed at the interface at 6 weeks after injection of rhBMP‐2. On radiography, spotty calcification appeared and enthesis‐like tissue was produced successfully in the tendon at 6 weeks after injection of rhBMP‐2. Use of the viscous collagen gel and rhBMP‐2 mixture increased the fusion rate between the bone tunnel and tissue graft. This study demonstrates that viscous collagen gel can be an effective carrier for rhBMP‐2 delivery into surgical sites, and that the injectable rhBMP‐2‐containing collagen gel may be applied for the enhancement of tendon–bone interface healing in the future. Copyright

Three-Dimensional Scapular Kinematics in Patients with Reverse Total Shoulder Arthroplasty during Arm Motion

Background There have been few reports on altered kinematics of the shoulder after reverse total shoulder arthroplasty (RTSA). We investigated differences in 3-dimensional (3D) scapular motions assessed using an optical tracking system between RTSA treated shoulders and asymptomatic contralateral shoulders during arm motion. Methods Thirteen patients who underwent RTSA were assessed for active arm elevation in 2 distinct elevation planes (sagittal plane flexion and scapular plane abduction). Their mean age was 72 years (range, 69 to 79 years) and the mean follow-up was 24.4 months (range, 13 to 48 months). The dominant side was the right side in all the 13 patients, and it was also the side treated with RTSA. Scapular kinematics was recorded with an optical tracking system. The scapular kinematics and the scapulohumeral rhythm (SHR) of the RTSA shoulders and asymptomatic contralateral shoulders were recorded and analyzed during arm elevation. Results There were no significant differences in internal/external rotation and anterior/posterior tilting of the scapula between shoulders during arm motion (p > 0.05). However, upward rotation of the scapula differed significantly during arm motion (p = 0.035 for sagittal plane flexion; p = 0.046 for scapular plane abduction). There were significant differences in the SHR between the two shoulders (p = 0.016 for sagittal plane flexion; p = 0.021 for scapular plane abduction). Conclusions The shoulder kinematics after RTSA showed significant differences from the contralateral asymptomatic shoulders. Increased upward rotation and decreased SHR after RTSA indicate that RTSA shoulders use more scapulothoracic motion and less glenohumeral motion to elevate the arm.