Previous cartilage surgery is associated with inferior patient-reported outcomes after knee arthroplasty.

PURPOSE: The hypothesis of the present study assumed that a history of focal cartilage lesions would not affect Knee Injury and Osteoarthritis Outcome scores (KOOSs) following knee arthroplasty compared to a matched national cohort of knee arthroplasty patients. METHODS: Fifty-eight knee arthroplasty patients with previous surgery for focal cartilage lesions (cartilage cohort) were compared to a matched cohort of 116 knee arthroplasty patients from the Norwegian Arthroplasty Register (control group). Age, sex, primary or revision arthroplasty, type of arthroplasty (total, unicondylar or patellofemoral), year of arthroplasty surgery and arthroplasty brand were used as matching criteria. Demographic data and KOOS were obtained through questionnaires. Regression models were employed to adjust for confounding factors. RESULTS: Mean follow-up post knee arthroplasty surgery was 7.6 years (range 1.2-20.3) in the cartilage cohort and 8.1 (range 1.0-20.9) in the control group. The responding patients were at the time of surgery 54.3 versus 59.0 years in the cartilage and control group, respectively. At follow-up the control group demonstrated higher adjusted Knee Injury and Osteoarthritis Outcome subscores than the previous focal cartilage patients with a mean adjusted difference (95% confidence interval in parentheses): Symptoms 8.4 (0.3, 16.4), Pain 11.8 (2.2, 21.4), Activities of daily living (ADL) 9.3 (-1.2, 18.6), Sport and recreation 8.9 (-1.6, 19.4) and Quality of Life (QoL) 10.6 (0.2, 21.1). The control group also demonstrated higher odds of reaching the patient-acceptable symptom state threshold for the Knee Injury and Osteoarthritis Outcome subscores with odds ratio: Symptoms 2.7 (1.2, 6.4), Pain 3.0 (1.3, 7.0), ADL 2.1 (0.9, 4.6) and QoL 2.4 (1.0, 5.5). CONCLUSION: Previous cartilage surgery was associated with inferior patient-reported outcomes after knee arthroplasty. These patients also exhibited significantly lower odds of reaching the patient-acceptable symptom state threshold for the Knee Injury and Osteoarthritis Outcome subscores. LEVEL OF EVIDENCE: Level III.

Patients with total hip arthroplasty were more physically active 9.6 years after surgery: a case-control study of 429 hip arthroplasty cases and 29,272 participants from a population-based health study.

BACKGROUND AND PURPOSE: Few studies report on long-term levels of physical activity after THA compared with a control population. This case-control study aimed to find the long-term habitual level of leisure-time physical activity after THA and compare it with a large control group. PATIENTS AND METHODS: A randomized sample of 856 patients, treated with primary THA, were identified from the Norwegian Arthroplasty Register. 429 (50%) responded to a questionnaire with a mean follow-up time of 9.6 years. We compared them with a control group of 29,272 (64%) from a population-based health study. Physical activity was measured with a questionnaire and categorized into groups according to the general recommendations for physical activity. RESULTS: 245 (63%) of the THA cases reported a level of leisure-time physical activity meeting the general recommendations, compared with 10,803 (39%) in the control group. The difference persisted at all ages (50-90 years). In sex, age, and BMI-adjusted regression models the chance of meeting the physical activity recommendations was higher in the THA group than in the control group (OR 2.9, 95% confidence interval 2.4-3.6). CONCLUSION: The majority of the patients with THA reported a level of leisure-time physical activity meeting the general recommendations for physical activity. THA patients were more physically active in their leisure time than a control group representing a normal population.

Automatic segmentation of human knee anatomy by a convolutional neural network applying a 3D MRI protocol.

BACKGROUND: To study deep learning segmentation of knee anatomy with 13 anatomical classes by using a magnetic resonance (MR) protocol of four three-dimensional (3D) pulse sequences, and evaluate possible clinical usefulness. METHODS: The sample selection involved 40 healthy right knee volumes from adult participants. Further, a recently injured single left knee with previous known ACL reconstruction was included as a test subject. The MR protocol consisted of the following 3D pulse sequences: T1 TSE, PD TSE, PD FS TSE, and Angio GE. The DenseVNet neural network was considered for these experiments. Five input combinations of sequences (i) T1, (ii) T1 and FS, (iii) PD and FS, (iv) T1, PD, and FS and (v) T1, PD, FS and Angio were trained using the deep learning algorithm. The Dice similarity coefficient (DSC), Jaccard index and Hausdorff were used to compare the performance of the networks. RESULTS: Combining all sequences collectively performed significantly better than other alternatives. The following DSCs (±standard deviation) were obtained for the test dataset: Bone medulla 0.997 (±0.002), PCL 0.973 (±0.015), ACL 0.964 (±0.022), muscle 0.998 (±0.001), cartilage 0.966 (±0.018), bone cortex 0.980 (±0.010), arteries 0.943 (±0.038), collateral ligaments 0.919 (± 0.069), tendons 0.982 (±0.005), meniscus 0.955 (±0.032), adipose tissue 0.998 (±0.001), veins 0.980 (±0.010) and nerves 0.921 (±0.071). The deep learning network correctly identified the anterior cruciate ligament (ACL) tear of the left knee, thus indicating a future aid to orthopaedics. CONCLUSIONS: The convolutional neural network proves highly capable of correctly labeling all anatomical structures of the knee joint when applied to 3D MR sequences. We have demonstrated that this deep learning model is capable of automatized segmentation that may give 3D models and discover pathology. Both useful for a preoperative evaluation.

The efficacy of strength or aerobic exercise on quality of life and knee function in patients with knee osteoarthritis. A multi-arm randomized controlled trial with 1-year follow-up.

OBJECTIVE: To evaluate the efficacy of strength exercise or aerobic exercise compared to usual care on knee-related quality of life (QoL) and knee function at 4 months and 1 year in individuals with knee osteoarthritis. METHODS: A three-arm randomized controlled trial (RCT) compared 12 weeks of strength exercise or aerobic exercise (stationary cycling) to usual care supervised by physiotherapists in primary care. We recruited 168 participants aged 35-70 years with symptomatic knee osteoarthritis. The primary outcome was The Knee Injury and Osteoarthritis Outcome Score (KOOS) QoL at 1 year. Secondary outcomes were self-reported function, pain, and self-efficacy, muscle strength and maximal oxygen uptake (VO2max) at 4 months and 1 year. RESULTS: There were no differences between strength exercise and usual care on KOOS QoL (6.5, 95% CI -0.9 to 14), or for aerobic exercise and usual care (5.0, 95% CI -2.7 to 12.8), at 1 year. The two exercise groups showed better quadriceps muscle strength, and VO2max at 4 months, compared to usual care. CONCLUSION: This trial found no statistically significant effects of two exercise programs compared to usual care on KOOS QoL at 1 year in individuals with symptomatic and radiographic knee osteoarthritis, but an underpowered sample size may explain lack of efficacy between the intervention groups and the usual care group. GOV IDENTIFIER: NCT01682980.

Medial patellofemoral ligament reconstruction is superior to active rehabilitation in protecting against further patella dislocations.

PURPOSE: Isolated reconstruction of the medial patellofemoral ligament (MPFL-R) has become the predominant stabilizing procedure in the treatment of recurrent lateral patellar dislocation (LPD). To minimize the risk of re-dislocations, isolated MPFL-R is recommended in patients with no significant trochlea dysplasia and tibial tuberosity trochlear groove distance < 20 mm on computed tomography (CT). Incidentally, these criteria are the same that are used to identify first time LPD patients where conservative treatment is recommended. The purpose of this study was therefore to compare MPFL-R with active rehabilitation for patients with recurrent LPD (RLPD) in absence of the above mentioned underlying anatomical high-risk factors for further patellar dislocations. METHODS: RLPD-patients aged 12-30 without underlying anatomical high-risk factors for further LPD were randomized into treatment either with isolated MPFL-R or active rehabilitation provided and instructed by a physiotherapist. All patients underwent diagnostic arthroscopy for concomitant problems. The main outcome measure was persistent patellar instability at 12 months. Knee function at baseline and 12 months was asses using the following patient reported outcomes measures (PROMS); KOOS, Kujala, Cincinnati knee rating, Lysholm score and Noyes sports activity rating scale. RESULTS: Between 2010 and 2019, 61 patients were included in the study (MPFL-R, N = 30, Controls, N = 31). Persistent patellar instability at 12 months was reported by 13 (41.9%) controls, versus 2 (6.7%) in the MPFL-group (RR 6.3 (95% CI 1.5-25.5). No statistically significant differences in activity level were found between the MPFL-group and the Controls at neither baseline nor follow up. The patients with persistent instability at 12 months did not score significantly lower on any of the PROMs compared to their stable peers, regardless of study group. CONCLUSION: Patients with recurrent patellar dislocations have a six-fold increased risk of persistent patellar instability if treated with active rehabilitation alone, compared to MPFL-R in combination with active rehabilitation, even in the absence of significant anatomical risk factors. Active rehabilitation of the knee without MPFL-R improves patient reported knee function after one year, but does not protect against persistent patellar instability.

Concomitant full-thickness cartilage lesions do not affect patient-reported outcomes at minimum 10-year follow-up after ACL reconstruction.

PURPOSE: To compare patients with a concomitant full-thickness cartilage lesion and anterior cruciate ligament (ACL) injury to patients with an isolated ACL injury at 10-15 years post ACL reconstruction. METHODS: This is a longitudinal follow-up of a cohort of 89 patients that were identified in the Norwegian National Knee Ligament Registry and included in the index study in 2007. The study group consisted of 30 patients that underwent ACL reconstruction and had a concomitant, isolated full-thickness cartilage lesion (International Cartilage Repair Society [ICRS] grade 3-4). Each study patient was matched with two control patients who underwent ACL reconstruction but had no cartilage lesions (ICRS grade 1-4) (n = 59). At a median follow-up of 10.2 years (range 9.9-15.6), 65 patients (74%) completed the Knee Injury and Osteoarthritis Outcome Score (KOOS), which was the main outcome measure, resulting in 23 pairs after matching. RESULTS: At a follow-up of 10-15 years after ACL reconstruction, no significant differences in KOOS were found between patients with a concomitant full-thickness cartilage lesion and patients without cartilage lesions. There was also no significant difference between the two groups when comparing the change over time in KOOS scores from preoperative to follow-up. Both groups showed significant improvement in all KOOS subscales from preoperative to follow-up, except for in the Symptoms subscale for the control group. The greatest improvement was in the QoL subscale for the study group. CONCLUSION: ACL-reconstructed patients with a full-thickness cartilage lesion did not report worse outcomes at 10-15 years after surgery compared with patients with an isolated ACL injury. Our findings support that there is no long-term negative effect of a concomitant cartilage lesion in an ACL-reconstructed knee. These findings should be considered when discussing treatment and informing about the expected long-term outcome after ACL reconstruction to patients with such combined injuries. LEVEL OF EVIDENCE: II.

Compensation claims after knee cartilage surgery is rare. A registry-based study from Scandinavia from 2010 to 2015.

BACKGROUND: Focal cartilage defects (FCDs) in the knee joint has a high prevalence. A broad range of treatment options exists for symptomatic patients. Knowledge of patient compensation claims following surgical treatment of FCDs is missing. The purpose of this study is to evaluate compensation claims filed to the Scandinavian registries for patient compensation following treatment of FCDs in the knee joint from 2010 to 2015 and identify possible areas of improvement. METHODS: A cross-sectional study design was used to obtain all complaints following surgical treatment of FCDs from the Scandinavian registries from 2010 to 2015. Data such as age, gender, type of treatment, type of complaint, reason of verdict and amount of compensation were collected and systematically analyzed. RESULTS: 103 patients filed a compensation claim. 43 had received debridement (41.7%), 54 microfracture (MF) (52.4%), 3 mosaicplasty (2.9%) and 3 autologous chondrocyte implantation (ACI) (2.9%). Of the 103 claims, 36 were granted (35%). 21 following debridement (58.3%), 13 after MF (36.1%), 1 following mosaicplasty (2.8%) and 1 after ACI (2.8%). The most common reason for complaint was infection (22.1%), of which 89% were granted. The average compensation was €24.457 (range €209 - €458.943). CONCLUSION: Compensation claims following surgical treatment of knee cartilage injuries in Scandinavia are rare. Establishing nationwide cartilage registries can add further knowledge on this troublesome disease.

Surgical site infection after hip fracture - mortality and risk factors: an observational cohort study of 1,709 patients.

Background and purpose - Surgical site infection (SSI) is a devastating complication of hip fracture surgery. We studied the contribution of early deep SSI to mortality after hip fracture surgery and the risk factors for deep SSI with emphasis on the duration of surgery.Patients and methods - 1,709 patients (884 hemi-arthroplasties, 825 sliding hip screws), operated from 2012 to 2015 at a single center were included. Data were obtained from the Norwegian Hip Fracture Register, the electronic hospital records, the Norwegian Surveillance System for Antibiotic Use and Hospital-Acquired Infections, and the Central Population Register.Results - The rate of early (≤ 30 days) deep SSI was 2.2% (38/1,709). Additionally, for hemiarthroplasties 7 delayed (> 30 days, ≤ 1 year) deep SSIs were reported. In patients with early deep SSI 90-day mortality tripled (42% vs. 14%, p < 0.001) and 1-year mortality doubled (55% vs. 24%, p < 0.001). In multivariable analysis, early deep SSI was an independent risk factor for mortality (RR 2.4 for 90-day mortality, 1.8 for 1-year mortality, p < 0.001). In univariable analysis, significant risk factors for early and delayed deep SSI were cognitive impairment, an intraoperative complication, and increasing duration of surgery. However, in the multivariable analysis, duration of surgery was no longer a significant risk factor.Interpretation - Early deep SSI is an independent risk factor for 90-day and 1-year mortality after hip fracture surgery. After controlling for observed confounding, the association between duration of surgery and early and delayed deep SSI was not statistically significant.

Recurrent lateral patella dislocation affects knee function as much as ACL deficiency - however patients wait five times longer for treatment.

BACKGROUND: Surgical treatment of young patients with recurrent lateral patella dislocation (RLDP) is often recommended because of loss of knee function that compromises their level of activity or even their daily life functioning. This situation is comparable to young patients with an anterior cruciate ligament (ACL) rupture. The purpose of this study was therefore to explore the time from injury to surgery and the pre-operative symptoms and knee function of young RLPD patients scheduled for stabilizing surgery and compare this group to age and sex-matched ACL-deficient patients. METHOD: Forty-seven patients with unilateral RLPD listed for isolated medial patellofemoral ligament reconstruction were included in the study (RLPD-group). This group was compared to an age, sex and BMI matched ACL patient group obtained from the Norwegian knee ligament registry (ACL-group) for the following outcome measures: the knee injury and osteoarthritis outcome score (KOOS) assessed on the day of surgery and time from injury to surgery. RESULTS: The RLPD-group scored significantly lower than the ACL-group for the three KOOS subscales "Pain" (73.6 vs. 79.8, p < 0.05), "Symptoms" (71.7 vs. 79.3, p < 0.05) and "ADL" (84.7 vs 89.5, p < 0.05). The lowest KOOS values were found for Sports/Recreation (53.5 vs. 51.3, p = 0.65) and Quality of life (37.6 vs. 36.7, p = 0.81). The average time from primary injury to surgery was 6 months for the ACL group and 31 months for the RLPD group. CONCLUSION: RLPD affected knee function as much as ACL deficiency, and was associated with more pain. Still the RLDP patients waited on average 5 times longer for surgery. TRIAL REGISTRATION: The patients with RLPD consisted of patients who were examined for possible recruitment for a concurrent prospective randomized controlled trial comparing conservative treatment and isolated surgical medial patellofemoral ligament (MPFL) reconstruction (Clinical trials no: NCT02263807 , October 2014).

Fast track hip fracture care and mortality - an observational study of 2230 patients.

BACKGROUND: Hip fracture patients are frail and have a high mortality. We investigated whether the introduction of fast track care reduced the 30-day mortality after hip fractures. METHODS: Fast track hip fracture care was established at our institution in October 2013. Data from the Norwegian Hip Fracture Register and electronic hospital records were merged for 2230 hip fracture patients operated in our department from January 2012 through December 2015. 1090 of these patients were operated before (conventional treatment group) and 1140 patients were operated after the introduction of fast track care (fast track group). Data were analysed by univariate analysis and binary logistic regression. RESULTS: Mortality did not differ significantly between the conventional treatment group and the fast track group at 30 days (7.9% vs. 6.5%), 90 days (13.5% vs. 12.5%) and one year (22.8% vs. 22.8%). Median admission time and time to surgery were significantly shorter in the fast track group than in the conventional treatment group (1.1 h vs. 3.9 h and 23.6 h vs. 25.7 h, both p <  0.0001). The 30-day reoperation rate was significantly lower in the fast track group compared to the conventional treatment group (odds ratio = 0.35 (95% CI: 0.15-0.84), p = 0.019). A composite 30-day outcome (reoperation, surgical site infection and/or death) was significantly less frequent in the fast track group (8.1%) than in the conventional treatment group (10.7%) in unadjusted analysis (p = 0.006), but not after adjusting for age, gender, cognitive impairment and ASA score (odds ratio = 0.85 (95% CI: 0.63-1.16), p = 0.31, 8.0% missing). Reoperations within 1 year, surgical site infections, 30-day readmissions and length of hospital stay did not differ significantly between the conventional treatment group and the fast track group. CONCLUSIONS: Fast track hip fracture care is safe. However, we observed no statistically significant change in 30-day, 90-day or 1-year mortality after the introduction of fast track hip fracture care. TRIAL REGISTRATION: The study was registered retrospectively at ClinicalTrials.gov (Protocol Record 284907 ) 6 December 2016.

Surgical reconstruction is a cost-efficient treatment option for isolated PCL injuries.

PURPOSE AND HYPOTHESIS: The main purpose of the study is to put focus on the costs related to treating posterior cruciate ligament (PCL) injuries and the possible implications of chosen treatment strategy to the respective institutions and society. METHODS: Costs of treating PCL injuries nonoperatively and for both single-bundle (SB) and double-bundle (DB) reconstruction were estimated. These costs were translated into equivalent quality-adjusted life years (QALY) given a threshold value of Euro (€) 70,000 per QALY. Expected gain in knee osteoarthritis outcome score (KOOS) quality of life (QoL) following surgery based on KOOS data from 112 patients was used as a basis for calculating the cost efficiency ratio. RESULTS: The average calculated cost of nonoperative treatment was €3382. Incremental cost for SB PCLR was €8585 (154%) and another increment of €5220 (61%) for DB PCLR using numbers from a European hospital. This is equivalent to increments of 0.074 (SB) and another 0.075 (DB) QALYs given the €70,000 threshold. For DB to be as cost efficient as SB reconstruction, the incremental gain in KOOS QoL has to be at the same level as for SB reconstruction compared to nonoperative treatment. CONCLUSION: Though surgical reconstruction adds a substantial cost to nonoperative treatment alone, it can be considered cost-effective. Double-bundle reconstruction is less cost efficient than SB reconstruction, but should probably still be considered the treatment of choice for certain patient categories. Randomized controlled trials looking at outcome following nonoperative, SB and DB PCL reconstruction are needed. The clinical relevance of this is that surgical reconstruction of PCL injuries is a cost-efficient treatment alternative in patients with an isolated PCL injury. This finding should be taken into consideration when deciding on how to treat these injuries. LEVEL OF EVIDENCE: III.

Microfracture is more cost-effective than autologous chondrocyte implantation: a review of level 1 and level 2 studies with 5 year follow-up.

PURPOSE: Focal cartilage defects in the knee may have devastating effect on the knee joint, where two of the main surgical treatment options are microfracture and autologous chondrocyte implantation. Comparative studies have failed to establish which method yields the best clinical results. A cost-effectiveness analysis of microfracture and autologous chondrocyte implantation would contribute to the clinical decision process. METHODS: A PubMed search identifying level I and level II studies with 5 year follow-up was performed. With the data from these studies, decision trees with associated service provision and costs connected to the two different techniques were designed. In addition to hospital costs, we included costs connected to physiotherapy following surgery. To paint a broader cost picture, we also included indirect costs to the society due to productivity loss caused by work absence. RESULTS: Four high-quality studies, with a follow-up of 5 years, met the inclusion criteria. A total of 319 patients were included, 170 undergoing microfracture and 149 autologous chondrocyte implantation. The re-operation rate was 23 (13.5%) following microfracture, and 18 (12.1%) for autologous chondrocyte implantation. Both groups achieved substantially better clinical scores at 5 years compared to baseline. Microfracture was more cost-effective when comparing all clinical scores. CONCLUSION: Microfracture is associated with both lower costs and lower cost per point increase in patient reported outcome measures. There is a need of well-designed, high-quality randomized controlled trials before reliable conclusions regarding cost-effectiveness in the long run is possible. LEVEL OF EVIDENCE: III.

Development of a pilot cartilage surgery register.

BACKGROUND: Norway has no prospective surveillance system to monitor the outcome of knee cartilage surgery. In 2004 the Norwegian Registry of Knee Ligament (NKLR) was successfully established, and has yielded useful information on the treatment of patients with both knee ligament and combined knee injuries. Patients with focal cartilage defects (FCDs) in their knees have reduced function and the treatment is difficult. There are geographical variations in treatment, and the generalizability from randomized controlled studies is low. These patients would benefit from a standardized long-time follow-up through a cartilage surgery register. The aim of the present study was to describe the development and report baseline challenges during the setting up of a pilot of a knee cartilage surgery register. METHODS: The study was designed as a prospective cohort study in the form of a register. Patients with full-thickness FCDs in the knee with International Cartilage Repair Society (ICRS) grade 3-4 on arthroscopy were included. The pilot included two hospitals; Oslo University Hospital (OUS), Ullevål and Akershus University Hospital (Ahus). RESULTS: We registered 58 patients with isolated FCDs, whereas 16 additional patients with full-thickness FCDs were registered through the NKLR. The patient cohort of patients with isolated FCDs consisted of 65% men and had a mean age of 29.8 years. The data are incomplete and the compliance varies from 18 to 73%. The distribution of mean KOOS scores were similar to previous patient cohorts with FCDs, with low scores for the KOOS Sport/Recreation and Quality of Life subscales. CONCLUSION: The level of compliance demonstrated a large difference between the two participating hospitals. The compliance for the isolated FCDs were low in both locations, although it reached an acceptable level in one hospital when patients with combined injuries from the NKLR were included. The forms were incompletely filled out by the surgeons postoperatively and need to be revised prior the establishment of a nation-wide register.

No negative effect on patient-reported outcome of concomitant cartilage lesions 5-9 years after ACL reconstruction.

PURPOSE: To compare patient-reported outcome 5-9 years after anterior cruciate ligament (ACL) reconstruction in patients with and without a concomitant full-thickness [International Cartilage Repair Society (ICRS) grade 3-4] cartilage lesion. METHODS: This is a prospective follow-up of a cohort of 89 patients that were identified in the Norwegian National Knee Ligament Registry and included in the current study in 2007, consisting of 30 primary ACL-reconstructed patients with a concomitant, isolated full-thickness cartilage lesion (ICRS grade 3 and 4) and 59 matched controls without cartilage lesions (ICRS grade 1-4). At a median follow-up of 6.3 years (range 4.9-9.1) after ACL reconstruction, 74 (84 %) patients completed the Knee Injury and Osteoarthritis Outcome Score (KOOS), which was used as the main outcome measure. Secondary outcomes included radiographic evaluation according to the Kellgren-Lawrence criteria of knee osteoarthritis (OA). RESULTS: At follow-up, 5-9 years after ACL reconstruction, no statistically significant differences in KOOS were detected between patients with a concomitant full-thickness cartilage lesion and patients without concomitant cartilage lesions. Radiographic knee OA of the affected knee, defined as Kellgren and Lawrence ≥2, was significantly more frequent in subjects without a concomitant cartilage lesion (p = 0.016). CONCLUSION: ACL reconstruction performed in patients with an isolated concomitant full-thickness cartilage lesion restored patient-reported knee function to the same level as ACL reconstruction performed in patients without concomitant cartilage lesions, 5-9 years after surgery. This should be considered in the preoperative information given to patients with such combined injuries, in terms of the expected outcome after ACL reconstruction and in the counselling and decision-making on the subject of surgical treatment of the concomitant cartilage lesion. LEVEL OF EVIDENCE: Prognostic; prospective cohort study, Level I.

Epidemiology of surgically treated posterior cruciate ligament injuries in Scandinavia.

PURPOSE: The main purpose of the study was to provide an overview of injury mechanisms, concomitant injuries, and other relevant epidemiological data for patients treated in Scandinavia with posterior cruciate ligament reconstruction (PCLR) following a posterior cruciate ligament (PCL) injury. METHODS: A total number of 1287 patients who underwent PCLR from 2004 to 2013 in the Scandinavian counties were included from the national ligament registries. The variables such as age, sex, activity, and graft used for reconstruction were collected. Then, injuries were sorted based on concomitant injuries. Finally, data from the different registries were compared. RESULTS: Average age of the treated patients was 32.7 years. Sex distribution ratio of male to female was 858:429 (66.7 %:33.3 %). Depending on definition, 26-37 % of the injuries treated were isolated PCL injuries. PCL injuries were most commonly encountered in sports with 35.4 % of the total number of PCL injuries in the study population. Soccer was the sport with the highest number of injuries (13.1 %). Cartilage lesions occurred in 26.1 % of PCL injuries and meniscal lesions in 21.0 %. Minimum one other additional ligament was injured in 62.2 %. CONCLUSION: Isolated PCL injuries are common, although the injury is most commonly associated with other ligament injuries. There is a high prevalence of cartilage injuries and meniscal lesions associated with PCL injuries. Sports are the leading cause of PCL injuries treated operatively. Epidemiological data are a necessary part of the basis for injury prevention in the future. The prevalence of concomitant injuries is also relevant and clinically important for the choice of surgical procedure and for the expected outcomes following surgery. LEVEL OF EVIDENCE: II.

No degeneration found in focal cartilage defects evaluated with dGEMRIC at 12-year follow-up.

Background and purpose - The natural history of focal cartilage defects (FCDs) is still unresolved, as is the long-term cartilage quality after cartilage surgery. It has been suggested that delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) is a biomarker of early OA. We aimed to quantitatively evaluate the articular cartilage in knees with FCDs, 12 years after arthroscopic diagnosis. Patients and methods - We included 21 patients from a cohort of patients with knee pain who underwent arthroscopy in 1999. Patients with a full-thickness cartilage defect, stable knees, and at least 50% of both their menisci intact at baseline were eligible. 10 patients had cartilage repair performed at baseline (microfracture or autologous chondrocyte implantation), whereas 11 patients had either no additional surgery or simple debridement performed. Mean follow-up time was 12 (10-13) years. The morphology and biochemical features were evaluated with dGEMRIC and T2 mapping. Standing radiographs for Kellgren and Lawrence (K&L) classification of osteoarthritis (OA) were obtained. Knee function was assessed with VAS, Tegner, Lysholm, and KOOS. Results - The dGEMRIC showed varying results but, overall, no increased degeneration of the injured knees. Degenerative changes (K&L above 0) were, however, evident in 13 of the 21 knees. Interpretation - The natural history of untreated FCDs shows large dGEMRIC variations, as does the knee articular cartilage of surgically treated patients. In this study, radiographic OA changes did not correlate with cartilage quality, as assessed with dGEMRIC.

Focal cartilage defects in the knee - a randomized controlled trial comparing autologous chondrocyte implantation with arthroscopic debridement.

BACKGROUND: Focal cartilage injuries in the knee might have devastating effect due to the predisposition of early onset osteoarthritis. Various surgical treatment options are available, however no statistically significant differences have been found between the different surgical treatments. This supports the suggestion that the improvement might be a result of the post-operative rehabilitation rather than the surgery itself. Autologous chondrocyte implantation (ACI) has become a recognized treatment option for larger cartilage lesions in the knee. Although ACI has been compared to other surgical treatment such as microfracture and mosaicplasty, it has never been directly compared to simple arthroscopic debridement and rehabilitation alone. In this study we want to increase clinical and economic knowledge about autologous chondrocyte implantation compared to arthroscopic debridement and physical rehabilitation in the short and long run. METHODS/DESIGN: We will conduct a randomized controlled trial to compare ACI with simple arthroscopic debridement (AD) and physiotherapy for the treatment of cartilage lesions in the knee. The study will include a total of 82 patients, both men and non-pregnant women, with a full thickness cartilage defect in the weight bearing area of the femoral condyles or trochlea larger than 2 cm2. The lesion must be symptomatic, with a Lysholm score less than 75. The two treatment groups will receive identical rehabilitation protocol according to a modification of Wondrasch et al., which is an active rehabilitation and education program divided into 3 phases: accommodation, rehabilitation and return to activity. The patients will be followed for 24 months, with additional late follow-ups at 5 and 10 years to monitor the potential onset of osteoarthtitis. The primary outcome measure will be the difference in the KOOS knee-related quality of life (QoL) subscore in the ACI group compared to the AD group at 2 years. A combination of self-explanatory questionnaires, clinical parameters, clinical hop tests and radiographs and Magnetic Resonance Imaging (MRI) will be used as secondary endpoints. DISCUSSION: This is the first study with a high level of evidence to compare ACI with simple debridement and physiotherapy for the treatment of isolated symptomatic full thickness lesions of the knee. TRIAL REGISTRATION: ClinicalTrial NCT02636881 (21 December 2015).

Evaluation of focal cartilage lesions of the knee using MRI T2 mapping and delayed Gadolinium Enhanced MRI of Cartilage (dGEMRIC).

BACKGROUND: Assessment of degenerative changes of the cartilage is important in knee cartilage repair surgery. Magnetic Resonance Imaging (MRI) T2 mapping and delayed Gadolinium Enhanced MRI of Cartilage (dGEMRIC) are able to detect early degenerative changes. The hypothesis of the study was that cartilage surrounding a focal cartilage lesion in the knee does not possess degenerative changes. METHODS: Twenty-eight consecutive patients included in a randomized controlled trial on cartilage repair were evaluated using MRI T2 mapping and dGEMRIC before cartilage treatment was initiated. Inclusion was based on disabling knee problems (Lysholm score of ≤ 75) due to an arthroscopically verified focal femoral condyle cartilage lesion. Furthermore, no major malalignments or knee ligament injuries were accepted. Mean patient age was 33 ± 9.6 years, and the mean duration of knee symptoms was 49 ± 60 months. The MRI T2 mapping and the dGEMRIC measurements were performed at three standardized regions of interest (ROIs) at the medial and lateral femoral condyle, avoiding the cartilage lesion RESULTS: The MRI T2 mapping of the cartilage did not demonstrate significant differences between condyles with or without cartilage lesions. The dGEMRIC results did not show significantly lower values of the affected condyle compared with the opposite condyle and the contra-lateral knee in any of the ROIs. The intraclass correlation coefficient (ICC) of the dGEMRIC readings was 0.882. CONCLUSION: The MRI T2 mapping and the dGEMRIC confirmed the arthroscopic findings that normal articular cartilage surrounded the cartilage lesion, reflecting normal variation in articular cartilage quality. STUDY IDENTIFIER: NCT00885729 , registered April 17 2009.

Norwegican Cartilage Project - a study protocol for a double-blinded randomized controlled trial comparing arthroscopic microfracture with arthroscopic debridement in focal cartilage defects in the knee.

BACKGROUND: Focal lesions to the articular cartilage in the knee might have demolishing consequences to the knee. There exists a wide range of possible surgical procedures targeting these injuries, however no significant differences have been found between these procedures. This may support that the improvement is a result of rehabilitation, and not the surgery itself. Arthroscopic microfracture (MF) treatment has gained popularity, and has become the treatment of choice in patients with knee cartilage defects globally. In this study we want to increase knowledge, both clinical and economic, about arthroscopic microfracture (AF) compared to arthroscopic debridement (AD) and physical rehabilitation both in the short run, and in the long run. METHODS/DESIGN: To compare arthroscopic microfracture with arthroscopic debridement and physiotherapy for the treatment of focal cartilage lesions in the knee, a long-term, double-blinded, randomized controlled multicenter trial will be conducted. A total of 114 men and non-pregnant women with a symptomatic focal full thickness cartilage lesion in the knee less than 2 cm2 will be included in the study. The two treatment allocations will receive identical rehabilitation, which is made up of 3 phases: accommodation, rehabilitation and return to activity. Follow up is 24 months, where all will be invited to participate in late follow ups after 5 and 10 years. The Knee Injury and Osteoarthritis Outcome Score (KOOS) knee-related quality of life (QoL) subscore is the primary endpoint. Clinical parameters, questionnaires and radiologic modalities (Magnetic Resonance Imaging (MRI) and x-ray) will be used as secondary endpoints. DISCUSSION: This is an ongoing multicenter study with a high level of evidence to compare arthroscopic microfracture with arthroscopic debridement and physiotherapy for the treatment of isolated symptomatic full thickness cartilage lesions in the knee joint. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT02637505 (December 15, 2015).

Relationship between CTX-II and patient characteristics, patient-reported outcome, muscle strength, and rehabilitation in patients with a focal cartilage lesion of the knee: a prospective exploratory cohort study of 48 patients.

BACKGROUND: C-telopeptide fragments of type II collagen (CTX-II) are created during articular cartilage breakdown and CTX-II is considered useful as a biomarker of osteoarthritis. The primary objective of the present study was to explore the relationship between urinary CTX-II concentration and patient characteristics, patient-reported outcome, muscle strength, and rehabilitation in patients with isolated focal knee cartilage lesions. Furthermore, the secondary objective was to examine differences in urinary CTX-II concentration between patients with focal cartilage lesions and healthy controls. METHODS: 48 patients (mean age 33.4 years, standard deviation 9.0) with a focal full-thickness (International Cartilage Repair Society grade 3 or 4) cartilage lesion on the medial or lateral femoral condyle were included. After baseline assessments, the patients completed a 3-month rehabilitation program and 44 patients attended the 3 month follow-up. Baseline and follow-up assessments consisted of urinary CTX-II, the Knee Injury and Osteoarthritis Outcome Score (KOOS), and isokinetic quadriceps and hamstring muscle strength measurements. CTX-II was also analysed in urine samples from 6 healthy individuals, serving as normal controls. Correlations were classified as very weak (correlation coefficient [r] < 0.20), weak (r = 0.20 - 0.39), moderate (r = 0.40 - 0.59), strong (r = 0.60 - 0.79), and very strong (r > 0.80). RESULTS: Except for age and quadriceps strength, no significant correlations were found between CTX-II concentrations and baseline characteristics, KOOS, or muscle strength. Except for age, all correlations were considered as weak or very weak. The patients with a focal cartilage lesion had significantly higher mean CTX-II concentration than the healthy control individuals both at baseline (p = 0.001) and at follow-up (p = 0.001). The mean CTX-II concentration tended to decrease during rehabilitation, but the reduction was not significant (p = 0.076). CONCLUSIONS: The current exploratory study demonstrated that patients with a focal cartilage lesion of the knee had higher concentrations of urinary CTX-II than healthy individuals. In addition, CTX-II concentration tended to decrease during rehabilitation. TRIAL REGISTRATION: ClinicalTrials.gov NCT00885729.