Prospective assessment of functional and clinical results of surgical patellar stabilization in rural and urban populations. Equal chance to success?

INTRODUCTION AND OBJECTIVE: Patella dislocation represents 3.3% of all knee injuries often leading to persistent instability. Medial patello-femoral ligament(MPFL) reconstruction is the standard method of treatment in the patellar instability. Rehabilitation after MPFL-R is a long and demanding procedure. The hypothesis presented reflects the idea that despite relatively good access to hospital care and surgical options, the post-operative rehabilitation care system is still inferior in rural areas versus the one offered in major cities and towns. MATERIAL AND METHODS: Between January 2015 - January 2018, 47 patients met the study inclusion criteria, diagnosed and operated on due to patellar instability. 8 patients were lost for full follow-up. Finally, 39 patients were included, divided into two groups - group A (19 from cities), group B (20 from rural area). Prospective KOOS and Kujala scales assessments were conducted: preoperative, 6 and 12 months after surgery. Knee isokinetic muscle strength was measured at 3 stages; prior to surgery, 6 and 12 months after reconstruction. RESULTS: All patients showed significant improvement measured in the KOOS and Kujala scales after the procedure, compared to the pre-operational results. Despite equal clinical improvement, patients from Group A(city) achieved better functional outcomes as presented in the results of knee extensor functional tests using a Biodex dynamometer. CONCLUSIONS: Rehabilitation after MPFL reconstruction improves muscle strength and clinical outcome. Patients from rural areas had inferior functional results in comparison to the patients from major cities, even 12 months after surgical patella stabilization. Despite the development of roads and transport according to the EU cohesion policy, there are still differences in rehabilitation results between rural and city areas.

Risk of Arthroplasty in Patients with Subchondral Insufficiency Fractures of the Knee: A Matched Study of the Implantable Shock Absorber using a Validated Predictive Model.

Subchondral insufficiency fractures of the knee (SIFK) can result in high rates of osteoarthritis and arthroplasty. The implantable shock absorber (ISA) implant is a titanium and polycarbonate urethane device which reduces the load on the medial compartment of the knee by acting as an extra-articular load absorber while preserving the joint itself. The purpose of this study was to evaluate whether partially unloading the knee with the ISA altered the likelihood of progression to arthroplasty utilizing a validated predictive risk model (SIFK score). A retrospective case-control (2:1) study was performed on patients with SIFK without any previous surgery and on those implanted with the ISA with the primary outcome being progression to arthroplasty compared with nonoperative treatment at 2 years. Baseline and final radiographs, as well as magnetic resonance imagings, were reviewed for the evaluation of meniscus or ligament injuries, insufficiency fractures, and subchondral edema. Patients from a prospective study were matched using the exact SIFK Score, a validated predictive score for progression to arthroplasty in patients with SIFK, to those who received the ISA implant. Kaplan-Meier analysis was conducted to assess survival. A total of 57 patients (38 controls:19 ISA) with a mean age of 60.6 years and 54% female were included. The SIFK score was matched exactly between cases and controls for all patients. The 2-year survival rate of 100% for the ISA group was significantly higher than the corresponding rate of 61% for the control group (p < 0.01). In ISA, 0% of the patients converted to arthroplasty at 2 years, and 5% (one patient) had hardware removal at 1 year. When stratified by risk, the ISA group did not have a significantly higher survival compared with low-risk (p = 0.3) or medium-risk (p = 0.2) controls, though it had a significantly higher survival for high-risk groups at 2 years (100 vs. 15%, p < 0.01). SIFK of the medial knee can lead to significant functional limitation and high rates of conversion to arthroplasty. Implants such as the ISA have the potential to alter the progression to arthroplasty in these patients, especially those at high risk.

An implantable shock absorber yields an 85% survival-from-arthroplasty rate through 5 years in working-age patients with medial compartment knee osteoarthritis.

PURPOSE: To evaluate the 5-year rate of survival without undergoing arthroplasty or high tibial osteotomy (HTO) in subjects with mild-to-moderate medial compartment knee osteoarthritis (OA) who were treated with an implantable shock absorber (ISA) system. METHODS: Three prospective, sequential, multicenter, international, single-arm clinical trials were conducted comprising subjects who received an ISA for symptomatic medial knee OA after failing ≥ 6 months of conservative therapy. Study outcomes were analyzed cumulatively and by enrollment group when all subjects' follow-up data exceeded the 2-year threshold after ISA implantation. Primary outcome was survival rate without conversion to arthroplasty/HTO. Secondary outcomes were changes in Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain and function scores after ISA implantation. RESULTS: All 171 enrolled subjects (age 51 ± 9 years, body-mass index 28.5 ± 3.5 kg/m2, 38% female; study knee Kellgren-Lawrence score 2.7 ± 0.9 points) were followed for a minimum of 2, and up to 5, years after device implantation. Overall, 90.6% (155/171) of subjects survived without requiring arthroplasty/HTO at last follow-up (mean 3.2 ± 1.6 years). The Kaplan-Meyer median 3- and 5-year survival-without-arthroplasty point estimates were 89.8% (95% CI 86.5‒95.7%) and 84.9% (95% CI 75.1‒91.1%), respectively. The median 3-year estimated survival rate for the most recent study (n = 81) was 97.3%. The mean WOMAC Pain score decreased 71% from baseline to last follow-up after ISA implantation, from 58 ± 13 to 16 ± 17 points (p < 0.0001). The Function score improved 69%, decreasing from 56 ± 18 to 17 ± 17 points (p < 0.0001). CONCLUSIONS: In younger patients with mild-to-moderate symptomatic medial compartment knee OA, implantation of the ISA device resulted in a 5-year survival rate of 85% from undergoing arthroplasty or HTO. The ISA system may be an effective treatment option for working-age patients with medial knee OA who are not candidates for or do not desire more invasive surgical approaches. LEVEL OF EVIDENCE: II.

Two-Year Results of the PHANTOM High Flex Trial: A Single-Arm Study on the Atlas Unicompartmental Knee System Load Absorber in Patients With Medial Compartment Osteoarthritis of the Knee.

The Atlas Knee System was designed to fill the gap between no longer effective conservative treatments and more invasive surgery for young patients with medial knee osteoarthritis (OA). This article reports on the 2-year results of a single-arm study of 26 subjects who previously reported favorable clinical outcomes 1 year post implantation. Western Ontario and McMaster Universities Osteoarthritis Index pain and function scores improved by a clinically meaningful amount relative to baseline, and subjects had a return to normal range of motion. This study confirmed that the benefit of a joint unloading device in the management of young patients with medial knee OA is maintained over 2 years. This trial was registered with ClinicalTrials.gov (NCT02711254).

Using the discrete wavelet transform in assessing the effectiveness of rehabilitation in patients after ACL reconstruction.

PURPOSE: The purpose of the current study was to assess the effectiveness of rehabilitation in patients after anterior cruciate ligament reconstruction (ACLR) using a wavelet analysis of the torque-time curve patterns of the extensors of the affected knee. The analysis aimed at the quantitative evaluation of irregularities in these torque-time patterns. METHODS: The study involved a group of 22 men who had had ACL reconstruction. The torque-time characteristics were recorded 3, 6 and 12 months after the surgery by an isokinetic dynamometer. They were then examined using the orthogonal Daubechies 4 (Db 4) and biorthogonal Bior 3.1 wavelets. RESULTS: A statistical analysis of the results revealed significant differences in values of the high-frequency energy stored in the details of the signal from the dynamometer between the first and last measurements, both for the Db 4 ( p ≤ 0.023) and Bior 3.1 ( p ≤ 0.01) wavelets. These differences were found in 73% of patients whose curve patterns were analysed using the Db 4 wavelet and in 82% of patients in the case of the Bior 3.1 wavelet. CONCLUSIONS: The wavelet transform proved to be an effective research tool in the qualitative evaluation of irregularities occurring in the curve patterns of the torque generated by the extensors of the ACL reconstructed knee. The findings of the study suggest that time-frequency analyses of these characteristics can be of practical importance, as they help assess the state of the patient's knee joint and his progress in rehabilitation after ACLR.

Feasibility of the Atlas Unicompartmental Knee System Load Absorber in Improving Pain Relief and Function in Patients Needing Unloading of the Medial Compartment of the Knee: 1-Year Follow-Up of a Prospective, Multicenter, Single-Arm Pilot Study (PHANTOM High Flex Trial).

In young patients with medial knee osteoarthritis (OA), surgical intervention may not be desirable due to preferences to avoid bone cutting procedures, return to high activity levels, and prolong implant survival. The Atlas Knee System was designed to fill the gap between ineffective conservative treatments and invasive surgery. This single-arm study included 26 patients, aged 25 to 65 years, who completed 12 months of follow-up. All dimensions of the Knee injury and Osteoarthritis Outcome Score (KOOS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Knee Society Score significantly improved from baseline to 12 months. About 96.2% and 92.3% of patients experienced a ⩾20% improvement in their KOOS pain and WOMAC pain scores, respectively, at 12 months. This study highlights the potential benefit of a joint unloading device in the management of young patients with medial knee OA. The trial is still ongoing and another analysis is planned at 24 months.

Isokinetic Identification of Knee Joint Torques before and after Anterior Cruciate Ligament Reconstruction.

The aim of this study was to evaluate the serial change of isokinetic muscle strength of the knees before and after anterior cruciate ligament reconstruction (ACLR) in physically active males and to estimate the time of return to full physical fitness. Extension and flexion torques were measured for the injured and healthy limbs at two angular velocities approximately 1.5 months before the surgery and 3, 6, and 12 months after ACLR. Significant differences (p ≤ 0.05) in peak knee extension and flexion torques, hamstring/quadriceps (H/Q) strength ratios, uninvolved/involved limb peak torque ratios, and the normalized work of these muscles between the four stages of rehabilitation were identified. Significant differences between extension peak torques for the injured and healthy limbs were also detected at all stages. The obtained results showed that 12 months of rehabilitation were insufficient for the involved knee joint to recover its strength to the level of strength of the uninvolved knee joint. The results helped to evaluate the progress of the rehabilitation and to implement necessary modifications optimizing the rehabilitation training program. The results of the study may also be used as referential data for physically active males of similar age.

Comparison of bioabsorbable interference screws and posts for distal fixation in anterior cruciate ligament reconstruction.

Comparison of the results of bioabsorbable interference screws and posts for hamstring graft distal fixation in ACL reconstructions are presented. The results of 20 patients with bioabsorbable screws were compared to 22 patients with posts. The assessement was based on Lysholm-Gillquist and Marshall scores and the KT-1000 device. In the study group the points gained were 38.9 in the Lysholm-Gillquist and 12.89 in the Marshall scale. The average KT-1000 difference was 2.46 mm. In the control group the points gained were 32.93 in the Lysholm-Gillquist and 11.47 in the Marshall scale. The average KT-1000 difference was 2.5 mm. There were 14 patients in the study group with interference screw problems; in 2 the implants were removed. (1) There are no differences in outcome using bioabsorbable interference screws and posts for distal fixation of hamstring ACL grafts. (2) The lack of bioabsorbtion with poly L-lactide interference screws is frequent and causes problems.

Rehabilitation after one-stage anterior cruciate reconstruction and osteochondral grafting.

At least 10-20% of all ACL reconstructions require additional cartilage repair. The aim of this study was to compare the activity recovered by patients after one-stage open ACL reconstruction and osteochondral autologous grafting of articular cartilage lesions and after isolated open ACL reconstruction. The study group included 21 patients with chronic ACL deficiency and grade III or IV cartilage lesion according to the ICRS scale who were treated with combined ACL reconstruction and osteochondral grafting in one step. The control group included 32 patients with chronic ACL insufficiency and no chondral deficit higher than grade I on the ICRS scale who underwent isolated reconstruction of the ligament. For the assessment, the Lysholm and Gillquist (L&G) score and the functional Marshall score were used. Both groups displayed a statistically significant improvement in the L&G score and the Marshall score between the preoperative and 12-month assessments. The mean gain in L&G score over this period was 30.66+/-7.79 in the study group and 31.65+/-6.96 in the control group. The difference between the control group and the study group was not significant. The difference between 12 months and initial assessment was counted. The mean gain in Marshall score was 9.05+/-3.81 in the study group and 10.71+/-3.43 in the control group. The difference between the initial and the 12-month evaluation was statistically significant (p=0.49). Return to normal activity was slower and patient satisfaction was lower during the first year after operation in the study group than in the control group, however the overall advantage of the one-step operation outweighs the slightly inferior functional results at 12 months.

Treatment outcome after one-stage reconstruction of the anterior cruciate ligament and mosaicplasty of the articular cartilage of the knee.

Background. Chronic rotational instability of the knee after damage to the anterior cruciate ligament (ACL) fairly quickly produces undesirable secondary changes in the joint. Concomitant damage may affect the meniscus or the articular cartilage of the femoral condyle. The purpose of our study was to compare outcome in patients who had undergone one-stage surgical repair of damage to the ACL and articular cartilage. Material and methods. We studied 17 patients with associated cartilage and ligament damage. The control group consisted of 36 patients with isolated ACL damage. Joint function was assessed according to the Marshall Scale and the Lysholm and Gilquist Scale. Examinations were performed before treatment, 2 and 6 weeks post-operatively, and again 3, 6 and 12 months after surgery. Results. In the course of rehabilitation we observed a slightly slower recovery in the patients with combined damage up to 6 months after surgery. There were no statistically significant differences in rehabilitation outcome at the end of the observation period Conclusions. This treatment method has the potential to permanently remedy knee slippage and cancel its early effects. The surgical outcome in repair of damage to the patellofemoral joint, combined with centralization of the knee's extension apparatus, are comparable at 2 years to centralization of the patella alone when the normal structure of the articular cartilage has been perserved.

Treatment outcome after patellar re-alignment by one-stage correction of the axis of the knee extensor and mosaicplasty of the patellofemoral joint.

Background. Patellar misalignment is often accompanied by damage to the chondral surface of the patello-femoral joint. The goal of surgical treatment is to address the primary cause by correcting the axis of knee flexion. In the Orthopedics and Traumatology Clinic in Lublin, Poland, we repair damaged cartilage and align the knee extensor in a one-stage operation. The goal of the present study is to compare the course of recovery and outcome in patients operated for recurrent patellar dislocation, in whom chondral damage in the patello-femoral joint is discovered intraoperatively. Material and methods. In a prospective experiment, 14 patients treated in our clinic from 2001 to 2003 were evaluated. The axis of the knee extensor was corrected both proximally and peripherally. Third- or fourth-degree chondral damage according to the ICRS scale was repaired by mosaicplasty. Outcome was evaluated by systematic assessment using the Marshall scale. The control group consisted of patients in whom only realignment was performed due to the absence of chondral damage. Results. Recovery was slower after combined treatment than in the control group. Two years post-operatively the functional outcomes in both groups were comparable, with no statistically significant differences. Conclusions. The treatment method described here gives reason to hope for long-term remediation of patellar misalignment, and removes the effects of earlier abnormalities. After 2 years, the functional outcome after repair to patello-femoral articular cartilage combined with patellar realignment are comparable to those achieved in patients not requiring repair of articular cartilage during patellar realignment.

[Repair of focal chondral lesions of femoral condyles treated with osteochondral autografts]. / Naprawy ogniskowych uszkodzen chrzastki stawowej klykci kosci udowych autogennymi przeszczepami chrzestno-kostnymi.

A series of 15 patients with focal chondral lesions of the femoral condyles were treated at the Orthopaedics Department of the University of Medical Sciences of Lublin between 1998-2000. The patients' age varied from 20 to 72 years and the follow-up period from 6 months to 2.5 years. Osteochondritis dissecans was observed in 9 patients. Articular cartilage defects associated with chronic ligament instability was noted in 5 cases and 1 patient suffered from a chondral fracture of the lateral femoral condyle during a traumatic luxation of the patella. The depth of the lesions was graded according to ICRS scale. Grade IV was found in 11 cases and the remaining 4 cases had grade III lesions. The defects were treated with osteochondral autografts using OATS instrumentation set. Results were prospectively evaluated according to the HSS score. The preoperative value of HSS score ranged from 28 to 51 points (average 40.3). During follow-up the score values ranged from 76 to 91 points (average 84.7 points). All patients regained full range of motion in the knee, although in one case arthroscopic release of intraarticular adhesions was performed 6 months after chondroplasty. The lowest HSS values at follow-up were found in elderly patients with concomitant mild degenerative changes in the lateral knee compartment and in the patello-femoral joint. All patients had MRI examination early post-op, then after 6, 12 and 24 months from the procedure. MRI confirmed proper structure of the grafted cartilage but bony parts of the graft did not integrate with the surroundings.