Jin Goo Kim

Clinical and Radiologic Outcomes After Meniscus Allograft Transplantation at 1-Year and 4-Year Follow-up

PURPOSE To assess the clinical and radiologic outcomes of meniscus allograft transplantation (MAT) with serial evaluation at 1 year and at 4 years. METHODS Among 151 patients who received MAT between March 2006 and June 2009, we prospectively recruited the patients who had undergone clinical and radiologic examinations at 1 year after the operation. The Lysholm score, International Knee Documentation Committee score, and Knee Society Score were determined. Plain radiography was used for evaluation of osteoarthritis, and magnetic resonance imaging (MRI) was used to assess the cartilage status and meniscal extrusion. RESULTS Thirty-nine patients with a mean age of 40 ± 9 years were recruited. The first visit was conducted at a mean of 13.6 months (range, 11 to 17 months) postoperatively, and the last visit was conducted at a mean of 50.4 months (range, 48 to 72 months) postoperatively. Of the patients, 29 were men. The lateral side was involved in 27 patients. The Lysholm knee score increased to a median value of 89 (range, 75 to 100) at the first visit and 88 (range, 76 to 100) at the second visit from a preoperative median value of 79 (range, 37 to 99), which was statistically significant according to the Kruskal-Wallis test. According to the Kellgren-Lawrence grade based on anteroposterior radiographs, 21 patients (54%) showed no arthrosis progression and the overall status of arthrosis on anteroposterior radiographs was significantly changed (P < .001). On MRI, 25 patients (64%) showed no cartilage status change and the overall status was not changed significantly (P = .178). The meniscal extrusion extent was 4.2 ± 0.4 mm at the first visit and 4.2 ± 0.6 mm at the second visit (P = .678), and the relative percentage of extrusion was 0.44 ± 0.16 and 0.51 ± 0.21, respectively (P = .059). The subgroup in which arthrosis had progressed on MRI showed a larger amount of change in the relative percentage of extrusion (P = .023). No correlation was observed between meniscal extrusion and various outcomes. CONCLUSIONS Repeat assessment at 4 years showed that MAT showed improvement in knee function, but it had decreased over time. Considerable meniscal extrusion was observed, but it did not increase during follow-up and did not show any correlation with other outcomes. Extrusion progression showed significant correlation with arthrosis progression. LEVEL OF EVIDENCE Level IV, therapeutic case series.

Pullout Fixation of Posterior Medial Meniscus Root Tears: Correlation Between Meniscus Extrusion and Midterm Clinical Results

Background: Medial meniscus posterior root tears (MMPRTs) lead to extrusion of the meniscus during weightbearing as well as loss of the ability of the meniscus to generate hoop stress. This loss of load-sharing ability leads to progressive arthritic changes. However, there have been no studies that correlate the correction of meniscus extrusion with clinical outcomes. Hypothesis: Decreased meniscus extrusion is associated with better clinical and radiographic outcomes compared with increased meniscus extrusion after MMPRT pullout fixation. Study Design: Case-control study; Level of evidence, 3. Methods: A total of 39 patients who underwent MMPRT pullout fixation and had been observed for more than 5 years were recruited for this study. The mean follow-up period was 69.8 months. Participants were categorized into 2 groups according to the direction of meniscus extrusion: group A (increased extrusion; 23 patients) and group B (decreased extrusion; 16 patients). Meniscus extrusion was assessed in the coronal plane on magnetic resonance imaging preoperatively and at 1 year postoperatively. The postoperative clinical outcomes (Lysholm and International Knee Documentation Committee [IKDC] scores) and radiographic results (Kellgren-Lawrence [K-L] grade and medial joint space) were compared between groups. Results: Meniscus extrusion in group A increased significantly from a mean (±SD) of 3.5 ± 0.9 mm preoperatively to 5.1 ± 1.4 mm at 1 year postoperatively (P < .001), whereas in group B, it decreased significantly from 4.1 ± 1.3 mm preoperatively to 3.5 ± 1.4 mm at 1 year postoperatively (P < .001). The K-L arthritis grade (0/1/2/3/4) significantly progressed in group A (from 2/12/9/0/0 preoperatively to 0/1/14/8/0 postoperatively, respectively; P = .009) but not in group B (from 1/11/4/0/0 preoperatively to 0/6/8/2/0 postoperatively, respectively; P = .274). The mean final Lysholm and IKDC scores in group B (88.1 ± 12.1 and 79.0 ± 11.4, respectively) were significantly better than those in group A (81.0 ± 9.0 and 71.1 ± 7.8, respectively) (P < .05). There was less medial joint space narrowing at final follow-up in group B (0.6 ± 0.8 mm) than in group A (1.1 ± 0.6 mm) (P = .015). Progression of the K-L arthritis grade was seen in 50% (8/16) of the patients in group B compared with 87% (20/23) of the patients in group A (P = .027). Conclusion: The current study demonstrates that in patients with MMPRTs, pullout fixation leads to favorable midterm outcomes, regardless of meniscus extrusion at 1-year follow-up. However, patients with decreased meniscus extrusion at postoperative 1 year have more favorable clinical scores and radiographic findings at midterm follow-up than those with increased extrusion at 1 year. This study indicates that one of the main goals of the repair of MMPRTs is to reduce meniscus extrusion as much as possible.

Anatomic Single-Bundle Anterior Cruciate Ligament Reconstruction Using the Modified Transtibial Technique

We present a technique for anterior cruciate ligament (ACL) reconstruction using hamstring tendon autograft with a modified transtibial technique. Our modified transtibial technique has the advantages of the conventional transtibial technique that is familiar to surgeons and that allows the press-fit fixing and enables us to make a relatively long femoral tunnel. To make the femoral tunnel at the anatomic position, the triangular, funnel-shaped bony trough was made to slip the eccentrically positioned guide pin into the anticipated anatomic center with a free-hand technique after marking the anatomic ACL footprint using a microfracture awl through the anteromedial portal. Gradual femoral reaming was performed with knee angle changes, which reduces the chances of posterior wall blowout, increases the femoral tunnel length, and avoids breakage of guide pin at the bending point. Our modified transtibial technique is anticipated to provide a more anatomic placement of the femoral tunnel during ACL reconstruction than the previous traditional transtibial techniques.

Arthroscopic Medial Meniscal Allograft Transplantation with Modified Bone Plug Technique

The meniscal allograft transplantation (MAT) has been reported to be an effective treatment in terms of pain relief and functional improvement in symptomatic meniscus-deficient knee. The medial MAT is usually performed with the bone plug technique or soft tissue fixation for root fixation. We describe medial MAT with modified bone plug technique that permits easy passage of posterior bone plugs and facilitates bone-to-bone healing. With this method, an anterior bone plug with a long cylindrical shape is prepared, and the posterior bone plug is prepared with a flat bone shell containing a cancellous portion. This modified technique facilitates graft passage as well as bone-to-bone healing.

Arthroscopic Lateral Meniscal Allograft Transplantation With the Key-Hole Technique

The efficacy of meniscus allograft transplantation (MAT) for the meniscus-deficient knee has been widely recognized as being excellent in terms of pain relief and functional improvement. Lateral MAT is usually performed with the bone bridge technique that uses a bone bridge connecting the anterior and posterior horns of an allograft. The slot position for the meniscal graft insertion is of great importance with the bone bridge technique, especially in the key-hole method. The purpose of this Technical Note is to describe lateral MAT using the key-hole technique in which an allograft with a bone bridge carved to accommodate the key-hole-shaped slot is properly secured to the slot.

Delayed Rehabilitation After Lateral Meniscal Allograft Transplantation Can Reduce Graft Extrusion Compared With Standard Rehabilitation

Background: Meniscal extrusion prevention would be important for restoring normal knee kinematics, even though the effect of graft extrusion after meniscal allograft transplantation (MAT) has not been clearly identified. Hypothesis: When compared with standard rehabilitation protocols, delayed rehabilitation after lateral MAT could reduce graft extrusion. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 53 patients who underwent lateral MAT with the keyhole technique from June 2011 to March 2015 were included. Graft extrusion and lateral compartment articular cartilage loss on magnetic resonance imaging, joint space width (JSW) on weightbearing radiographs, and clinical outcomes (including subjective scores and functional tests) of 25 patients who underwent standard rehabilitation (group S) after lateral MAT were compared with those of 28 patients who underwent delayed rehabilitation (group D), which included immobilization during the first 3 weeks and use of unloading braces for 9 weeks. Results: Mean ± SD follow-up times for groups S and D were 25.7 ± 6.4 and 24.5 ± 7.1 months, respectively. Although the postoperative clinical outcomes did not differ between the groups, graft extrusion (3.2 ± 1.5 mm vs 1.8 ± 1.6 mm) and relative percentage of extrusion (32.2% ± 14.6% vs 17.3% ± 16.6%) were greater in group S than in group D (P < .001 for both). The percentage of patients with graft extrusion (≥3 mm) was 52% in group S and 21.4% in group D. JSWs on Rosenberg view decreased by 0.1 mm in group S but increased by 0.3 mm in group D (P = .035). Kellgren-Lawrence grade and modified Outerbridge grade progressed by 44% and 44% among patients in group S and by 17.9% and 21.4% among patients in group D, respectively. There were significant correlations between the coronal graft extrusion and postoperative JSWs on full extension (–0.452) and Rosenberg (–0.410) views, Kellgren-Lawrence grade (0.727), and modified Outerbridge grade (0.732) on magnetic resonance imaging (P < .001 for all). Conclusion: Compared with standard rehabilitation, delayed rehabilitation showed less coronal graft extrusion and joint space narrowing on weightbearing and reduced the progression of arthrosis, although the rehabilitation protocols showed no differences in clinical outcomes.

Comparison of Poly-L-Lactic Acid and Poly-L-Lactic Acid/Hydroxyapatite Bioabsorbable Screws for Tibial Fixation in ACL Reconstruction: Clinical and Magnetic Resonance Imaging Results

Background The purpose of this study was to compare the clinical and radiological results of 2 different tibial fixations performed using bioabsorbable screws with added hydroxyapatite (HA) and pure poly-L-lactic acid (PLLA) screws in anterior cruciate ligament (ACL) reconstruction. Methods A total of 394 patients who underwent arthroscopic ACL reconstruction between March 2009 and June 2012 were retrospectively reviewed. Of those, 172 patients who took the radiological and clinical evaluations at more than 2 years after surgery were enrolled and divided into 2 groups: PLLA group (n = 86) and PLLA-HA group (n = 86). Both groups were assessed by means of the Lysholm score, International Knee Documentation Committee (IKDC) subjective knee score, and Tegner activity score. Stability was evaluated using the KT-2000 arthrometer. Magnetic resonance imaging was performed to evaluate tibial tunnel widening, screw resorption, osteoingeration, and foreign body reactions. Results The PLLA-HA group showed significant reduction in the extent of tibial tunnel widening and foreign body reactions and significant increase in screw resorption compared to the pure PLLA group (p < 0.001 for both). In contrast, postoperative Lysholm score, Tegner activity score, IKDC score, and side-to-side difference on the KT-2000 arthrometer showed no significant differences between groups (p = 0.478, p = 0.906, p = 0.362, and p = 0.078, respectively). The PLLA group showed more significant widening in the proximal tibial tunnel than the PLLA-HA group (p = 0.001). In the correlation analysis, proximal tibial tunnel widening revealed a positive correlation with knee laxity (r = 0.866) and a negative correlation with Lysholm score (r = −0.753) (p < 0.01 for both). Conclusions The HA added PLLA screws would be advantageous for tibial graft fixation by reducing tibial tunnel widening, improving osteointegration, and lowering foreign body reactions. Even though no clinically significant differences were noted between the pure PLLA group and PLLA-HA group, widening of the proximal area of the tibial tunnel showed a tendency to increase knee laxity measured using the KT-2000 arthrometer.

A Randomized, Multicenter, Phase III Trial to Evaluate the Efficacy and Safety of Polmacoxib Compared with Celecoxib and Placebo for Patients with Osteoarthritis

Background The aim of this study was to evaluate the safety and analgesic efficacy of polmacoxib 2 mg versus placebo in a superiority comparison or versus celecoxib 200 mg in a noninferiority comparison in patients with osteoarthritis (OA). Methods This study was a 6-week, phase III, randomized, double-blind, and parallel-group trial followed by an 18-week, single arm, open-label extension. Of the 441 patients with knee or hip OA screened, 362 were randomized; 324 completed 6 weeks of treatment and 220 completed the extension. Patients were randomized to receive oral polmacoxib 2 mg (n = 146), celecoxib 200 mg (n = 145), or placebo (n = 71) once daily for 6 weeks. During the extension, all participants received open-label polmacoxib 2 mg. The primary endpoint was the change in Western Ontario and McMaster Universities (WOMAC)-pain subscale score from baseline to week 6. Secondary endpoints included WOMAC-OA Index, OA subscales (pain, stiffness, and physical function) and Physicians and Subjects Global Assessments at weeks 3 and 6. Other outcome measures included adverse events (AEs), laboratory tests, vital signs, electrocardiograms, and physical examinations. Results After 6 weeks, the polmacoxib-placebo treatment difference was −2.5 (95% confidence interval [CI], −4.4 to −0.6; p = 0.011) and the polmacoxib-celecoxib treatment difference was 0.6 (CI, −0.9 to 2.2; p = 0.425). According to Physicians Global Assessments, more subjects were “much improved” at week 3 with polmacoxib than with celecoxib or placebo. Gastrointestinal and general disorder AEs occurred with a greater frequency with polmacoxib or celecoxib than with placebo. Conclusions Polmacoxib 2 mg was relatively well tolerated and demonstrated efficacy superior to placebo and noninferior to celecoxib after 6 weeks of treatment in patients with OA. The results obtained during the 18-week trial extension with polmacoxib 2 mg were consistent with those observed during the 6-week treatment period, indicating that polmacoxib can be considered safe for long-term use based on this relatively small scale of study in a Korean population. More importantly, the results of this study showed that polmacoxib has the potential to be used as a pain relief drug with reduced gastrointestinal side effects compared to traditional nonsteroidal anti-inflammatory drugs for OA.

Refractory patellar tendinopathy treated by arthroscopic decortication of the inferior patellar pole in athletes: Mid-term outcomes

BACKGROUND This study aimed to evaluate the clinical outcomes of arthroscopic decortication of the inferior patellar pole in athletes with refractory chronic patellar tendinopathy. METHODS Thirty-seven athletes in whom conservative management for at least six months failed underwent arthroscopic patellar tendon debridement and decortication of the inferior pole of the patella. Clinical outcomes were evaluated using subjective knee scores and isokinetic muscle strength tests. The average duration taken and sports participation level were also assessed. RESULTS The mean follow-up period was 51.3 ± 14.8 months. At the last follow-up, all improvements in subjective knee scores including Lysholm score, International Knee Documentation Committee (IKDC) subjective score, Victorian Institute of Sport Assessment -Patella (VISA-P) score, and Kujala score were statistically significant (p<.001). Tegner activity scale improved from 6.5±1.0 to 8.9±0.8 (p<.001). Limb symmetry index for extensor peak torque improved from 71.4±19.6% to 92.7±21.7% (p<.001). Thirty-two (86.5 %) athletes were able to return to full sports activities in a mean 3.5±1.7months, and 27 (73%) athletes maintained their previous sports activity level at the last follow-up. Symptoms recurred in two (5.2%). CONCLUSIONS Arthroscopic decortication of the inferior pole of the patella showed satisfactory clinical results and high rates of return to sports at mid-term follow-up in professional athletes with refractory chronic patellar tendinopathy. This technique could be an invasive, safe, and effective treatment for chronic patellar tendinopathy in professional athletes who want a faster return to sports. LEVEL OF EVIDENCE Level IV, case series.

Single-leg vertical jump test as a functional test after anterior cruciate ligament reconstruction

BACKGROUND The aim of this study was to identify the correlations between the single-leg vertical jump (SLVJ) test and subjective and objective tests which were used widely for determining return-to-sports (RTS) after anterior cruciate ligament reconstruction (ACLR). METHODS Seventy-five patients (29.5 ± 9.2 years) who underwent ACLR between May 2012 and Jan 2014 were included. Subjective knee scoring systems including subjective International Knee Documentation Committee (IKDC) score, Lysholm score, Tegner activity scale, and ACL-Return to Sports after Injury (ACL-RSI) scale were assessed. Objective tests were also performed. RESULTS The limb symmetry index (LSI) for SLVJ test and single-leg hop for distance (SLHD) test was 89.4 ± 14.9% and 90.7 ± 11.7%. LSI for SLVJ test was correlated to subjective IKDC scores (r = 0.26, P = 0.024), Tegner activity scale (r = 0.64, P < 0.001), ACL-RSI scale (r = 0.61, P < 0.001), LSI for SLHD (r = 0.45, P < 0.001), Co-contraction (r = -0.57, P < 0.001), Shuttle run (r = -0.52, P < 0.001), and Carioca (r = -0.54, P < 0.001) tests. In isokinetic strength tests, extensor peak torque (r = 0.30, P = 0.009) and extensor strength deficit (r = -0.41, P < 0.001) were correlated with LSI for SLVJ test. CONCLUSION There were considerable correlations between SLVJ test and subjective IKDC scores, Tegner activity scale, ACL-RSI scale, isokinetic extensor muscle strength, and all other functional tests. SLVJ test could be used conveniently to determine RTS after ACLR in outpatient clinics. LEVEL OF EVIDENCE Level IV, case series.