Rose Zätterström

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.

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.

Proprioceptive defects after an anterior cruciate ligament rupture – the relation to associated anatomical lesions and subjective knee function

Abstract A disturbed proprioception has been described in patients with an anterior cruciate ligament (ACL) deficient knee. The relation to demographic data and to different commonly associated anatomical lesions, as well as to subjective knee function, was prospectively studied in 16 consecutive patients after an acute knee ligament injury. All patients had a complete rupture of the ACL, but variable associated anatomical lesions. The threshold to detect a passive motion, as a measure of their proprioceptive ability, was registered repeatedly during the first year after injury. Four of the patients had consistently severe and persistent deficits at 1, 2 and 8 months. These four individuals had more chondral lesions and a lower subjective rating of their knee function than the remaining patients. In the whole group there were significant correlations between the recorded thresholds and associated chondral lesions, meniscal lesions and the subjective rating of knee function. We found no significant relation between age, gender, activity level, grade of mechanical laxity increase or a medial collateral ligament rupture, and the proprioceptive recordings. Thus, morphological lesions other than a rupture of the ACL seem to contribute to the proprioceptive deficits after a knee ligament injury, and the patients’ ability to detect a passive motion showed a relation to subjective knee function from the time of injury onwards.

Individual factors affecting stabilometry and one-leg hop test in 75 healthy subjects, aged 15-44 years

The aims of this study were: 1) to investigate whether single‐limb stabilometry and a one‐leg hop test are influenced by age, sex, height, weight or activity level in healthy subjects, 2) to examine possible differences between the right and the left leg, 3) to determine Limb Symmetry Index (LSI) values, and 4) to study the relation between the stabilometric variables, that is, average speed (AS) and amplitude of center of pressure (CP) movements. Seventy‐five healthy subjects (39 women) were studied, with a mean age of 29.5 years (SD 8.2, range 15–44), mean height 175 cm (SD 8.6, range 155–194), mean weight 67.8 kg (SD 9.7, range 50–90) and median value 8 (quartiles 8–9, range 7–10) on a 1–10 activity‐level scale. AS was higher among the men compared to the women and increased with increasing age. The females hopped shorter distances than the males. The hop distance decreased with increasing age among the women. Height, weight and activity level within the actual range had no significant influence on stabilometric or hop‐test values. When comparing patients with healthy subjects, they should be matched according to sex and age, with an age difference of less than 10 years within pairs.

Compression or distraction of the anterior cruciate injured knee. Variations in injury pattern in contact sports and downhill skiing.

Abstract100 consecutive patients with a recent anterior cruciate ligament injury were examined with respect to type of sports activity that caused the injury, mechanism of injury and the occurrence of collateral ligament and meniscal lesions. There were 53 medial collateral ligament injuries, 12 medial, 35 lateral and 11 bicompartmental meniscal lesions. 59 patients were injured during contact sports, 30 in downhill skiing and 11 in other recreational activities, traffic accidents or at work. An associated medial collateral, ligament tear was more common in skiing (22/30) than during contact sports (23/59), whereas a bicompartmental meniscal lesion was found more frequently in contact sports (9/59) than in skiing (0/30). Weightbearing was reported by 56/59 of the patients with contact sports injuries and by 8/30 of those with skiing injuries. Non-weightbearing in the injury situation led to the same rate of MCL tears (18/28) as those reporting weightbearing (35/72) but significantly more intact menisci (19/28 vs 23/72). Thus, contact sports injuries were more often sustained during weightbearing, with a resultant joint compression of both femuro-tibial compartments as shown by the higher incidence of bicompartmental meniscal lesions. This might be an important prognostic factor for future joint disease and arthrosis. The classic “unhappy triad” was a rare finding (8/100) and we suggest that this entity should be replaced by the “unhappy compression injury”.

Disability in anterior cruciate ligament insufficiency: An analysis of 19 untreated patients

We analyzed the knee function in 19 consecutive patients with chronic instability after an anterior cruciate ligament rupture. Muscle strength, standing balance, activity level, functional knee score, and a performance test were evaluated. Reduced quadriceps muscle strength compared with the noninjured limb was associated with reduced performance as measured by the one-leg hop test and the Lysholm knee score. No weakness in the hamstrings was found. The patients had impaired standing balance with increased body sway in the frontal plane when standing on both the injured and noninjured limb.