The effect of exercise, prewrap, and athletic tape on the maximal active and passive ankle resistance to ankle inversion. Manfroy PP, Ashton-Miller JA, Wojtys EM. American Journal of Sports Medicine Vol. 25, No. 2, 1997;156.
Like so many articles before it, this article reinforces the observation that ankle taping does little to prevent inversion (active or passive). It does, however, add a new observation: use of prewrap improved maximal resistance to inversion by more than 10%. This is an important piece of information because it has always been assumed that because prewrap decreases the contact area for tape it therefore would create a less supportive taping. Apparently, this concept has been challenged by this study. A short review of the literature at the beginning of this article discusses what is known about taping, and points out the generally held belief that ankle taping may shorten reaction time for the peroneal muscles. Therefore, the effect of taping is probably more proprioceptive than supportive.
Patellofemoral pain syndrome: a critical review of the clinical trials on nonoperative therapy. Arroll B, Ellis-Pegler E, Edwards A, Sutcliffe G. American Journal of Sports Medicine Vol. 25, No. 2, 1997; 207.
The authors performed a critical review of the literature from 1966-1995 for randomized controlled trials evaluating the effectiveness of conservative management of patellofemoral pain syndromes. Their search criteria were broad, including patellofemoral pain associated with articular cartilage damage. Although there were 50 articles evaluating numerous approaches, only five studies met the inclusion criteria. Several interesting findings emerged. One study indicated that the use of an elastic supportive sleeve for patellofemoral pain actually increased the patient's pain. It generally appears that continuing activity, avoiding inciting activity positions, and strengthening of the quadriceps are highly successful. It also appears that in patients with new patellofemoral pain, the natural history is to resolve without sequelae.
These observations make claims of success less impressive. For example, use of McConnell taping (used to help track the patella properly) has not been shown to maintain tracking, yet initial claims of success were as high as 96%. The question that remains is how much of this success is due to natural resolution and how much is due to the therapy.
The role of the knee brace in the prevention of anterior knee pain syndrome. BenGal S, Lowe J, Mann G, et al. American Journal of Sports Medicine Vol. 25, No. 1, 1997;118.
Given the indictment of the previous article on knee braces and patellofemoral pain syndrome, it is interesting that this study demonstrated a protective effect when asymptomatic patients wore a knee brace (with a silicon patellar support ring) while initiating a strenuous exercise program. Males in the control group (not wearing a brace with exercise) had a significant incidence of anterior knee pain compared to the braced group. It also appears as though the brace did not reduce the performance of those patients who wore it during exercise and allowed improvement in their physical fitness parameters.
The relationship between passive joint laxity and functional outcome after anterior cruciate ligament injury. Snyder-Macklar L, Fitzgerald K, Bartolozzi AR, Cioccotti MG. American Journal of Sports Medicine Vol. 25, No. 2, 1997;191.
Over the last decade, criticism regarding the use of objective measures versus subjective assessments has occurred with the low back, shoulder, and knee. The observation is that although some "objective" measures do not improve over time, the functional status of the patient does. For practical purposes, the subjective measures are a better evaluation tool of patient recovery and return to normal activity. This study addresses the use of laxity as a measure of improvement after ACL injury. In other words, measurement tools of outcome success that include or weigh laxity as an important discriminator may artificially inflate the degree of disability. The other implication is that if these tools are used to determine which patients should go on to surgery, numbers of patients may have unnecessary surgery. It appears that there are a number of patients who can adequately compensate for loss of ACL function, and that although their degree of passive laxity remains unchanged, their function improves and is sufficient even for sports activity. Those with isolated damage to the ACL fare better than those with multiple tissue damage.
Quadriceps muscle contraction protects the anterior cruciate ligament during anterior tibial translation. Aune AK, Cawley PW, Ekeland A. American Journal of Sports Medicine Vol. 25, No. 2, 1997;187.
Over the last few years it has become apparent that the quadriceps effect on tibial translation is position dependent. When performing open chain exercises (e.g., seated knee extensions), the quadriceps may provide some stability in the range of 70-80 degrees or more. This study questions the concept that the quadriceps can cause ACL damage via a mechanism of overcontraction. It has classically been assumed that sudden stopping or other maneuvers that cause violent quadriceps contraction cause the tibia to be translated forward, injuring the ACL. This study seems to indicate that perhaps there is another explanation (in particular with skiing injuries), because it appears that the quadriceps contraction acts to stabilize the knee. The authors feel that ACL injury with skiing is probably due more to rotations and translations that are imposed by a large moment arm created by the ski-boot complex.
Biomechanical analysis of the effectiveness of in-line skating wrist guards for preventing wrist fractures. Giacobetti FB, Sharkey PF, Bos-Giacobetti MA, et al. American Journal of Sports Medicine Vol. 25, no. 2, 1997;223.
Using cadavers, the authors designed a biomechanical fracture model to test the ability of in-line skating wrist guards (indicated that they were made by a leading manufacturer; no name or model) to protect from fractures. Their conclusion was that the wrist guards tested were not effective in preventing wrist fractures and recommended more study and redesign of the wrist guard based on biomechanical investigations.
Cervical spine alignment in the immobilized football player: radiographic analysis before and after helmet removal. Swenson T, Lauerman WC, Blanc RO, et al. American Journal of Sports Medicine Vol 25, No. 2, 1997;226.
When cervical trauma is suspected with a football injury, the patient is placed on a spine board for transport with the neck immobilized. The question and dilemma often arises is whether to remove the helmet or not. The authors of this study use radiographic evaluation of subjects immobilized on a spine board with no shoulder padding or helmet, with both the helmet and shoulder padding, and just with the shoulder pads (helmet removed). Interestingly, there was no difference in cervical alignment between subjects who wore no padding or helmet and those wearing both the helmet and padding. However, with those subjects that had the helmet removed and shoulder padding left on, there was a statistically significant increase in cervical lordosis (extension), especially in the upper cervical area. It appears the helmet helps maintain a more neutral alignment when shoulder pads are also worn. The authors recommend that football players be immobilized on a spine board with both the helmet and shoulder pads left in place. Next month we will continue with a number of other interesting articles.
Thomas Souza, DC, DACBSP
Faculty, Palmer West
San Jose, California