Thomas Fridén

Prevalence of Tibiofemoral Osteoarthritis 15 Years After Nonoperative Treatment of Anterior Cruciate Ligament Injury: A Prospective Cohort Study

Background The occurrence of osteoarthritis (OA), associated meniscal injuries, meniscectomy, and patient-related measures for patients treated nonoperatively after anterior cruciate ligament (ACL) injuries have not been well described in the literature in terms of natural history. Hypothesis Patients with ACL injury can achieve a low occurrence of tibiofemoral OA and good knee function when treated without ACL reconstruction. Study Design Cohort study (prognosis); Level of evidence, 2. Methods One hundred consecutive patients with an acute, complete ACL injury were observed for 15 years. All patients were primarily treated with activity modification and without ACL reconstruction. To achieve improved functional stability, supervised physical therapy was initiated early after injury. The patients were examined using anteroposterior weightbearing radiography. The Knee injury and Osteoarthritis Outcome Score (KOOS) was used to quantify knee-related symptoms and knee function. Results Seventy-nine patients consented to radiographic examination and 93 completed the KOOS questionnaire. Thirteen patients (16%), all of whom were among the 35 patients whose knees were meniscectomized, developed radiographic tibiofemoral OA. In contrast, none of the remaining nonmeniscectomized and radiographed knees developed OA (n = 44) (P < .0001). Sixty-three patients (68%) had an asymptomatic knee. Twenty-two patients (23%) had undergone ACL reconstruction with a mean time of 4 years after injury. Conclusion The study had a favorable long-term outcome regarding incidence of radiographic knee OA, knee function and symptoms, and need for ACL reconstruction. Although risk factors for posttraumatic OA are multifactorial, the primary risk factor that stood out in this study was if a meniscectomy had been performed. Early activity modification and neuromuscular knee rehabilitation might also have been related to the low prevalence of radiographic knee OA. In patients with ACL injury willing to moderate activity level to avoid reinjury, initial treatment without ACL reconstruction should be considered.

A stabilometric technique for evaluation of lower limb instabilities

Stabilometry is a technique designed to register pos tural equilibrium control. This investigation used a com puterized strain gauge force plate to measure sway movements in the frontal plane with the patient standing on one leg. Fifty-five young healthy individuals were studied as a reference group and to determine the reproducibility of the method. The clinical population consisted of 14 patients with unilateral injuries to the lateral ligaments of the ankle. These were measured, both with and without an ankle brace. The different parameters used to describe the body sway could well discriminate between the injured and the uninjured leg. When the brace was used the effect was obvious and none of the parameters showed any significant differ ence compared to the uninjured leg.

Activity Level and Subjective Knee Function 15 Years After Anterior Cruciate Ligament Injury A Prospective, Longitudinal Study of Nonreconstructed Patients

Background The activity level and subjective knee function after an anterior cruciate ligament (ACL) injury treated without reconstruction have not been well elucidated. Hypothesis Patients with ACL injury can achieve good knee function and satisfactory long-term activity level when treated by early activity modification combined with rehabilitation. Study Design Cohort study (prognosis); Level of evidence, 2. Materials and Methods One hundred patients with an acute total ACL injury were observed for 15 years. All patients initially underwent arthroscopic surgery and a rehabilitation program. They were advised to modify their activity level, especially by avoiding contact sports. Patients with recurrent giving-way episodes and/or secondary meniscal injuries that required fixation (n = 6) were subsequently excluded and underwent reconstruction (n = 22). Sixty-seven patients with unilateral nonreconstructed ACL injury remained at the 15-year follow-up. The Lysholm knee score, Tegner activity level, and a visual analog score for global knee function were recorded at regular intervals. At the final follow-up, patients were further evaluated with the Knee injury and Osteoarthritis Outcome Score (KOOS) and International Knee Documentation Committee (IKDC) subjective knee evaluation form. Results Forty patients resumed their preinjury activity level or higher within 3 years. The median activity level 15 years after injury had decreased from 7 to 4 according to Tegner activity scale (P < .001). The mean Lysholm knee score was 96 and 95, 1 and 3 years after injury, respectively, but declined to 86 after 15 years (P < .001). Forty-nine patients had good/excellent results, and 14 had fair (n = 6) or poor function (n = 8) at 15 years. Patients injured in contact sports scored lower in the quality of life sub-scale of KOOS than those injured in noncontact sports (P < .05). Thirteen of the 67 patients (19%) were reoperated with an arthroscopic procedure because of knee symptoms. Conclusion Early activity modification and neuromuscular rehabilitation resulted in a good knee function and an acceptable activity level in the majority of the nonreconstructed patients. The decline in activity level of patients engaged in contact sports at the time of injury affected their subjective quality of life more than patients involved in noncontact sports.

Severe aseptic synovitis of the knee after biodegradable internal fixation : a case report

Biodegradable rods made of polyglycolide (Dexon, Biofix) or lactide-glycolide copolymer (Vicryl) have been used for the past 5 years for internal fixation of a variety of fractures and osteotomies (Böstman et al. 1989, 1990b). Experience from using such rods for fixation of intraarticular osteochondral lesions seems to be less extensive. We report a case of severe synovial reaction to biodegradable rods used for fixation of osteochondritis dissecans of the knee and discuss possible reasons for the increased risk of foreign-body reactions when these rods are used intraarticularly.

The Effect of Physiotherapy on Standing Balance in Chronic Anterior Cruciate Ligament Insufficiency

Body sway movements in the frontal plane in a single- limbed stance test were used to assess postural control in 26 patients with chronic anterior cruciate ligament insufficiency. The injured and the noninjured legs were tested before the patients were committed to physio therapy for 3 to 6 months. Follow-up tests were made after 3, 12, and 36 months. Significant disturbance of the balance of both legs was found before training, com pared with a reference group of normal subjects. Values of the noninjured leg were normalized after 3 months of training, but the injured leg still showed an increased body sway. Normal balance parameters on the injured side were found at examination after 12 months. Follow-up examination after 36 months proved persis tent normalization of the single-limbed balance on both sides.

Proprioception in the nearly extended knee. Measurements of position and movement in healthy individuals and in symptomatic anterior cruciate ligament injured patients

Proprioception of the knee was measured in 19 healthy individuals to evaluate whether there were any differences between extension and flexion movements from two different starting positions. The threshold before detecting a passive movement, visual estimation on a protractor of a passive change in position (30o angular change) and active reproduction of the same angular change were registered. The reference population was tested twice to study normal variation and reproducibility, followed by the evaluation of 20 patients with chronic, symptomatic and unilateral anterior cruciate ligament (ACL)-deficient knees. In the normal population no differences were found between the right and the left leg, men and women, or measurements made at the first and at the second test occasion. The thresholds from a starting position of 20o were lower for extension than for flexion. When comparing the thresholds for extension between the 20o and the 40o starting position, lower values were lower from the 40o starting position. than from the 20o starting position. The active reproduction of an angular change of 30o was more accurate during flexion (30o–60o) than during extension (60o-30o). There were no differences in the reproduction tests or in thresholds from the 40o starting position between the patients and the normal group, but the patients had higher thresholds from the 20o starting position, in movements towards both extension 1.0o (range 0.5o–12.0o) and flexion 1.5o (range 0.5o–10.0o) than the normal group 0.75o (range 0.5o–2.25o) (P=0.01) and 1.0o (range 0.5o–3.0o) (P=0.06), respectively. Thus, information of passive movements in the nearly extended knee position was more sensitive towards extension than towards flexion in threshold tests and the sensitivity improved closer to full extension, which implies a logical joint protective purpose. In this nearly extended knee position, which is the basis for most weight-bearing activities, patients with symptomatic ACL-deficient knees had an impaired awareness in detecting a passive movement. There were no differences in the more flexed position or in the reproduction tests between the patients and the normal group, and reproduction tests in the present form seem less appropriate to use in the evaluation of ACL injuries.

Balance in Single-Limb Stance in Patients With Anterior Cruciate Ligament Injury Relation to Knee Laxity, Proprioception, Muscle Strength, and Subjective Function

Background It has been shown previously that an anterior cruciate ligament injury may affect postural control, measured by balance in single-limb stance. To our knowledge, no studies have reported the influence of measures of impairment on postural control after such an injury. Purpose To assess the influence of knee laxity, proprioception, and muscle strength on balance in single-limb stance and to study the correlation between balance in single-limb stance and subjective estimation of extremity function. Study Design Cross-sectional study; Level of evidence, 3. Methods A total of 36 patients with a unilateral, nonoperated, nonacute anterior cruciate ligament injury were examined with regard to anterior knee laxity, proprioception, muscle strength, and stabilometry (amplitude and average speed of the center of pressure movements). Subjective estimation of extremity function was measured on a visual analog scale. Results The multiple regression analysis showed that high knee laxity values were associated with high amplitude values and low average speed. Poor proprioception and high muscle strength values were associated with low average speed among the women only. Low amplitude values correlated with better subjective function. Conclusion Anterior knee laxity, proprioception, and muscle strength seem to play a role in maintaining balance in single-limb stance. Patients with low amplitude values in stabilometry were those with better subjective function.

Rehabilitation following acute anterior cruciate ligament injuries – a 12-month follow-up of a randomized clinical trial

The efficacy of two non‐operative rehabilitation programs was studied in a consecutive randomized controlled clinical trial of 100 patients after 12 months subsequent to an acute anterior cruciate ligament (ACL) injury. Follow up of randomization to two training models was evaluated after 3 and 12 months: A self‐monitored training program (SM) of traditional mobility and muscle strength training of the injured leg was compared to a supervised (SV) training model exercising postural function in closed kinetic‐chains. Nearly 50% of the patients in the SM group required supervision after 6 weeks. An intention‐to‐treat analysis was performed and showed significantly better values in most of the results of the supervised group at 3 and 12 months. An alternative analysis of subgroups showed a significant difference between transferred male patients and original SV male patients at 3 months but not at 12 months, indicating the importance of initial guiding after an ACL injury. No such difference was observed in the female patients.

Evaluation of an external device measuring knee joint rotation: an in vivo study with simultaneous Roentgen stereometric analysis

An external device (“rottometer”) specially designed to measure knee joint rotation was developed and evaluated with respect to its validity. Simultaneous measurements were made with the rottometer and Roentgen stereometric analysis (RSA) in five patients with implanted tantalum markers in the tibia and femur. Measurements of internal and external rotation were made at 90° and 60° of knee flexion using 3, 6 and 9 N m torques. The coefficients of determination (r2) between the results obtained with the rottometer and RSA were around 0.9 for the total rotation. The rottometer consistently overestimated the rotation by about 100% and this systematic error was most constant at 90° flexion for the different torques. The magnitude of this error from soft tissue deformation as well as the rotatory movements in the hip, foot and ankle joints must be considered when using external devices to measure knee rotation in clinical studies. The most accurate registrations were found in 90° flexion with 9 N m force (r2 = 0.94).

Clinical measurements of proprioception, muscle strength and laxity in relation to function in the ACL-injured knee.

A knee injury with anterior cruciate ligament (ACL) rupture may cause deficits in proprioception, increased laxity and decreased muscle strength. Although it may be common knowledge that these factors affect knee function, only a few studies have been performed where this has been investigated in the clinical situation, and the results are not conclusive. The purpose of this study was therefore to investigate how and to what extent proprioception, laxity and strength affect knee joint function and evaluate if the methods commonly used for estimating these factors clinically seem to be relevant. The study encompassed 36 patients with ACL deficiency. A single-leg hop test for distance and subjective rating of knee function were defined as dependent variables and analyzed separately in stepwise linear regression models where proprioception, knee joint laxity, hamstrings and quadriceps strength, age and sex were defined as independent variables. Higher threshold values (poorer proprioception), increased side-to-side difference of anterior laxity and poorer strength significantly predicted shorter length of the hop test. Higher rating of subjective function corresponded to female gender, lesser side-to-side difference of anterior laxity and better proprioception.