Purpose: Many young adults develop knee osteoarthritis (OA) and have poor knee function long-term after an anterior cruciate ligament (ACL) injury, regardless of treatment with ACL reconstruction (ACLR) or rehabilitation alone. There is a need to investigate how to provide better outcomes. We aimed to describe 10-year radiographic and symptomatic knee OA, patient-reported symptoms, and function in participants who followed the Delaware-Oslo ACL cohort treatment algorithm. We further aimed to compare outcomes between participants who chose early (<6 months) ACLR with pre- and postoperative rehabilitation, delayed (>6 months) ACLR with pre- and postoperative rehabilitation, and progressive rehabilitation alone.

The Orthopaedic Section of the American Physical Therapy Association (APTA) has an ongoing effort to create evidence-based practice guidelines for orthopaedic physical therapy management of patients with musculoskeletal impairments described in the World Health Organization's International Classification of Functioning, Disability, and Health (ICF). The purpose of these revised clinical practice guidelines is to review recent peer-reviewed literature and make recommendations related to meniscus and articular cartilage lesions. J Orthop Sports Phys Ther. 2018;48(2):A1-A50. doi:10.2519/jospt.2018.0301.

Purpose: The risk of post-traumatic knee osteoarthritis is significantly increased after anterior cruciate ligament (ACL) injury. Changes in joint space width (JSW) are a radiographic feature of osteoarthritis which can occur within years after ACL injury and reconstruction. The purpose of this study was to describe the JSW and mechanical alignment of patients 5 years after complete unilateral ACL rupture managed non-operatively or with reconstruction. We also aimed to determine if Kellgren-Lawrence (KL) grades of knee osteoarthritis and mechanical knee alignment were associated with JSW measurements at 5 years. We hypothesized that patients with knee osteoarthritis as defined by KL grading and varus mechanical alignment would demonstrate narrower JSW than those without knee osteoarthritis and those with neutral or valgus alignment. Methods: Eighty-three athletes with an acute, isolated ACL injury who participated in cutting and pivoting activities prior to injury were included. Weightbearing posterior-anterior bent knee radiographs were completed at 5 years and analyzed using SigmaView software (Agfa HealthCare Corporation, Greenville, SC) to determine JSW, KL grades, and mechanical alignment in the medial tibiofemoral compartment of each limb. JSW was measured at a minimum and at a fixed location in each medial tibiofemoral joint (25% of distance from medial to lateral edge of femur (JSW.25)). Interlimb differences in JSW measures were calculated (involved minus uninvolved). Offsets (2° for women, 4° for men) were added to anatomical alignment measures to estimate the mechanical alignment of the knee. The offsets used have previously been shown to be reliable in calculating mechanical alignment from full limb films. Mechanical alignment for each patient was categorized as varus alignment ( < −2°), neutral alignment (between −2° and +2°), or valgus alignment ( > +2°). An independent t-test was used to determine if JSW measurements differed between those with and without medial osteoarthritis as defined by KL grades. A one-way analyses of variance (ANOVA) was used to determine if mechanical alignment was associated with JSW measurements. Results: The average age of the 83 patients at 5 years was 35.0 ± 11.8 years, 39% were women, and 23% were managed non-operatively. Patients completed radiographs an average 5.3 ± 0.7 years after ACL reconstruction or completion of non-operative rehabilitation. The average medial compartment minimum JSW was 4.8 ± 1.2 mm in the involved knee and 4.9 ± 1.0 mm in the contralateral knee. The average JSW.25 was 6.4 ± 1.3 mm in the involved knee and 6.3 ± 1.1 mm in the contralateral knee. Fourteen percent of the 83 patients had a KL grade of 2 or greater in the medial compartment of the involved knee at 5 years. The medial minimum JSW in the involved knee of patients with a KL grade of 2 or greater (OA) was 0.5 millimeters smaller than the uninvolved knee but 0.1 millimeters larger in patients with a KL grade of 0 or 1 (nonOA) (p: 0.115, OA: −0.5 ± 1.8 mm, nonOA: 0.1 ± 1.0 mm). Interlimb differences in JSW.25 did not differ between those with and without OA (p: 0.611, OA: 0.1 ± 1.6 mm, nonOA: 0.2 ± 0.8 mm). Fifty-eight percent of patients demonstrated radiographically neutral alignment at 5 years, 22% demonstrated varus alignment, and 20% demonstrated valgus alignment. Mechanical alignment was not associated with the interlimb difference in minimum JSW (p: 0.511, Varus: −0.2 ± 1.3 mm, Neutral: −0.1 ± 1.2 mm, Valgus: 0.2 ± 1.0 mm) or JSW.25 (p: 0.756, Varus: 0.1 ± 0.9 mm, Neutral: 0.2 ± 1.0 mm, Valgus: 0.3 ± 0.9 mm). Conclusions: Patients with advanced radiographic signs of post-traumatic knee osteoarthritis after ACL injury (KL grade of 2 or greater) demonstrated joint space narrowing while JSW was similar to the contralateral limb in patients without osteoarthritis. Knee malalignment did not correspond to JSW in the ACL-injured knee at 5 years; however, its long-term influence on post-traumatic knee osteoarthritis progression is not known. Recognition of the long-term effects of malalignment on knee joint health may affect surgical decisions to use alignment-modifying procedures such as osteotomies after ACL injury.

Purpose: Knee joint osteoarthritis (OA) is common following anterior cruciate ligament (ACL) injury and reconstruction (ACLR). Abnormal joint loading is one key mechanism in the development of OA, and evidence of altered loading has been demonstrated following ACL injury and ACLR. Identifying a link between joint loading and OA is a critical step in better understanding and preventing early onset knee joint OA. Therefore, the purpose of this study was to determine whether knee joint moments and contact forces early after injury and surgery were associated with radiographic knee OA 5 years after ACLR. Methods: Fourteen patients (6 F, 8 M, age 32.5 ± 12.0 yrs) with acute, unilateral ACL injury participating in cutting and pivoting activities were included in this study. All underwent ACLR using a hamstring autograft or soft tissue allograft. Testing consisted of gait analysis with electromyography (EMG) at 4 time points: pre-operatively after ROM, effusion, and pain were resolved (baseline), immediately following 10 sessions of pre-operative rehabilitation (post-training), 6 months after ACLR following criterion-based rehabilitation (6 months), and 2 years after ACLR (2 years). Standard motion analysis methods were used to obtain stance phase kinematics and kinetics during walking at a self-selected speed. Kinetic measures of interest included external peak knee flexion moment (PKFM), peak knee adduction moment (PKAM), and knee adduction moment impulse during the first 50% of stance (KAMI). Knee joint contact forces were derived using an EMG-driven Hill-type musculoskeletal model to estimate muscle forces. Muscle forces were used to calculate peak medial compartment contact forces (pkMC) during stance phase. Weight-bearing posterior-anterior (PA) bent knee (30 degree) radiographs were taken 5 years after ACLR and graded using the Kellgren-Lawrence system. Presence of OA was defined as a grade ≥ 2 in the medial compartment. Fisher's exact test and independent t-tests were performed to test differences in demographics, pkMC, PKFM, PKAM, and KAMI between those with and without radiographic OA in the medial compartment (OA, nonOA) 5 years after ACLR. Results: Nine subjects had OA in the index knee 5 years after ACLR, 5 did not. The OA and nonOA groups were not different with respect to BMI, sex, age, pre-injury activity level, time from injury to pre-training, graft type, or concomitant injuries (p > 0.10). In general, the OA patients walked slower (1.58 m/s) than the nonOA patients (1.73 m/s). There was no difference in pkMC between groups at baseline (p = .209, nonOA: 2.97 ± 0.96 BW, OA: 2.45 ± 0.31 BW) (Figure 1). After pre-operative training, the OA group had significantly lower pkMC than the nonOA group (p = .032, nonOA: 3.41 ± 1.00 BW, OA: 2.49 ± 0.29 BW). Six months after ACLR the lower pkMC persisted in the OA group (p = .038, nonOA: 3.24 ± 0.63 BW, OA: 2.31 ± 0.61 BW). Two years after ACLR, there were no longer significant differences between groups as the OA group loading increased (p = .598, nonOA: 3.06 ± 0.60 BW, OA: 2.94 ± 0.16 BW). No significant differences between groups in any kinetic measures were present at any time point. However, both KAM and KAMI demonstrated similar trend of loading to pkMC (Figure 2). Conclusions: An association existed between early medial compartment unloading and the presence of radiographic medial knee OA 5 years later. pkMC demonstrated superior ability to differentiate between the presence of OA 5 years after ACLR compared to kinetic measures, although both KAM and KAMI did demonstrate similar patterns of loading to pkMC. The more comprehensive approach undertaken by the musculoskeletal model to estimate joint loading, including use of frontal and sagittal plane kinetics along with co-contraction estimates via EMG input, may provide enhanced insight into the development of OA as compared to kinetic measures alone. Patients with OA had lower involved joint contact forces (unloading) relative to the uninvolved before and 6 months after ACLR, with loading becoming similar between groups 2 years after ACLR. This persistent (months) unloading followed by reloading as evidenced by 2 year pkMC data may be a perfect storm for the development of knee OA after ACL injury and reconstruction, and the time frame between injury and 6 months after ACLR may represent a critical period during which articular cartilage health is highly sensitive to joint unloading and cartilage deconditioning.Figure 2External knee adduction moment during stance phase of walking. Bars represent ± 1 SD.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Purpose: Intra-articular hyaluronic acid (HA) injections are a non-surgical treatment for knee osteoarthritis (OA) that have the potential to reduce pain and improve functional ability. Despite potential benefits, not all patients that receive HA injections have an optimal response. Several different HA formulations are available and a comparative analysis of outcomes is lacking in the literature. Therefore, the purpose of this study was to quantify the functional benefit of two different HA formulations for individuals with knee OA. Methods: The Knee Outcome Survey (KOS) and Global Rating Score (GRS) from patients who received HA injections for knee OA were analyzed. Patients with bilateral injections completed a questionnaire for each limb. Baseline KOS and GRS scores prior to injection and scores 4-6 weeks after the last injection were compared between subjects who received 5 Sodium Hyaluronate (Supartz) injections (n = 226) or a single Hylan G-F 20 (Synvisc-One) injection (n = 368). "Responders" to the HA injections were operationally defined as 1) Patients who had a KOS change score greater than 10 points or 2) Patients who showed any increase in KOS scores. Self-reported knee function, ranked as "Severely Abnormal", "Abnormal", "Nearly Normal", or "Normal" was evaluated at baseline to stratify groups if a significant interaction effect was found. "Normal" subjects were subjects without functional limitations, but may have had pain or were known to have chondral lesions. A repeated measures ANOVA was used to assess change in KOS score between injection types and over time. Chi-square analysis was used to determine differences in the responder rate between injection types and determine if there was a relationship between change perception of function (KOS and GRS) and baseline self-reported knee function. Results: 594 knees were assessed and time between first injection and follow-up was 78 +/- 13 days for patients who received Sodium Hyaluronate and 46 +/- 15 days for patients who received Hylan G-F 20. There was a significant Self-Function by Time interaction effect (p≤0.002) and those with lower reported self-functional score (abnormal, severely abnormal) demonstrated greater improvement in KOS and GRS scores at follow-up (Figures 1 and 2). There was no Injection Type by Time interaction effect and no difference in responder rates when stratified by injection type suggesting no difference in outcomes between the multi or single injection (p>0.455). Most patients patients demonstrated some improvement on the KOS at follow-up, although a smaller number of individuals achieved a 10 point change on the KOS (Table 1). Conclusions: HA injections offer small, but significant improvements in self-reported function for the majority of patients with OA. There was no additional functional benefit to using one particular formulation. Patients who report their knee function as abnormal or severely abnormal at baseline are most likely to have a larger response at follow-up. Future evaluations should assess pain and performance in addition to self-perception outcomes.View Large Image Figure ViewerDownload Hi-res image Download (PPT)View Large Image Figure ViewerDownload Hi-res image Download (PPT)

eight skeletal sites and knee structure in asymptomatic young to middleaged females without any clinical signs of osteoarthritis. Methods: One hundred and sixty healthy, females (29–50yr) without symptoms of osteoarthritis underwent magnetic resonance imaging of the knee. BMD was measured at the spine, hip, total body and forearm by dual energy x-ray absorptiometry, and SoS, BUA and SI were measured at the calcaneus by quantitative ultrasound (QUS). BMD and QUS measures were tested for an association with cartilage volume, defects, and bone marrow lesions (BMLs). Results: medial cartilage volume was positively associated with bmd at the total body, femoral neck, and ward’s triangle (all p < 0.05). Non-significant associations in the same direction existed at the spine (p =0.07), and trochanter (p = 0.10). Findings in the lateral compartment were similar. The presence of medial cartilage defects showed a nonsignificant association with bmd at the spine (p = 0.05). Bmd was not associated with lateral cartilage defects or bmls. No associations were observed with qus measures at the calcaneus. Conclusions: Whilst site-specific BMD is associated with cartilage volume at the knee in asymptomatic females aged 29–50yr, peripheral BMD measures, and QUS measures of the calcaneus, showed no associations with knee structure. These data suggest that the association between cartilage volume and axial/ lower limb BMD may relate to common local, possibly biomechanical, factors.

Objective. To determine the effect of quadriceps strength and joint stability on gait patterns after anterior cruciate ligament injury and reconstruction.Design. Cross-sectional comparative study in which four groups underwent motion analysis with surface electromyography.Background. Individuals following anterior cruciate ligament rupture often demonstrate reduced knee angles and moments during the early stance phase of gait. Alterations in gait can neither be ascribed to instability nor to quadriceps weakness alone when both are present.Methods. Twenty-eight individuals with complete anterior cruciate ligament rupture (10 patients with acute rupture. 8 patients following reconstruction with quadriceps strength >90% of the uninvolved side [strong-anterior cruciate ligament reconstructed group], and 10 patients after reconstruction with qUadriceps strength <8% of the Uninvolved side [weak-anterior cruciate ligament reconstructed group]), and 10 uninjured subjects underwent an examination of their lower extremity to collect kinematics, kinetics, and electromyography during walking and jogging. Anterior cruciate ligament reconstruction was arthroscopically assisted and a double loop semitendinosis-gracilis autograft or allograft was used as a graft Source. All reconstructed Subjects had stable knees, full range of motion, and no effusion or pain at the time of testing (more than three months after surgery).Results. Knee angles and moments of the strong group were indistinguishable front the Uninjured group during early stance of both walking and jogging. The weak subjects had reduced knee angles and moments during walking. and jogged similarly to the deficient subjects. Regression analysis revealed a significant effect between early stance phase knee angles and moments and quadriceps strength during both walking and jogging.Conclusion. Inadequate quadriceps strength contributes to altered gait patterns following anterior cruciate ligament reconstruction.

The objective of this study was to determine the effect of quadriceps strength and joint instability on gait patterns after anterior cruciate ligament (ACL) injury and reconstruction. Individuals following ACL rupture often demonstrate truncated knee flexion angles and moments during weight acceptance. Alterations in gait cannot be ascribed to instability or quadriceps weakness alone when both are present. Twenty-eight individuals with complete ACL rupture (10 patients with acute rupture, 8 patients following reconstruction with strong quadriceps (quadriceps index ≥ 90%), and 10 patients after reconstruction with weak quadriceps (quadriceps index ≤ 80%)), and 10 uninjured subjects underwent motion analysis to determine lower extremity kinematics, kinetics, and muscle activation during walking and jogging. All subjects who underwent reconstruction received an arthroscopically assisted ACL reconstruction with either semitendinosis-gracilis autograft or allograft, had stable knees, full range of motion, and no effusion or pain at the time of testing (three to six months after surgery). The results showed that knee angles and moments of the strong group were indistinguishable from the uninjured group in early stance during walking and jogging. The weak subjects had reduced knee angles and moments during walking, and jogged similar to the deficient subjects. Regression analysis revealed a significant relationship between early stance phase knee angles and moments and quadriceps strength during both walking and jogging. The weak and deficient groups showed a similar muscular response involving diminished quadriceps and increased hamstring activity during jogging. Inadequate quadriceps strength contributes to the altered gait patterns following ACL reconstruction and indicates that rapid strengthening is needed following ACL injury or reconstruction to allow a safe return to high level activities.

Eastlack, M.; Snyder-Mackler, L.; Gillespie, M.; Axe, M.; Bartolozzi, A. Author Information