Alberto Gobbi, Elizaveta Kon, Massimo Berruto, Giuseppe Filardo, Marco Delcogliano, Lorenzo Boldrini, Lyndon Bathan, Maurilio Marcacci,

Damaged cartilage covering the articular surfaces of the knee joint can be a very difficult condition to treat for orthopaedic surgeons; Recently, second-generation autologous chondrocyte implantation (ACI) has been used and has produced satisfactory results in the short-term.

34 of an original 38 patients treated for full-thickness patellofemoral chondral lesions with second-generation ACI, were assessed 5 years post-operation. 8 patients had received a secondary arthroscopy or biopsy. These revealed the repaired surface to be nearly normal with biopsy samples characterized as hyaline-like in appearance.

Hyaluronan-based scaffold seeded with autologous chondrocytes can be a viable treatment for patellofemoral chondral lesions.

All the scores used demonstrated a statistically significant improvement at 2 and 5 years’ follow-up

Am J Sports Med June 2009 vol. 37 no. 6 1083-1092

M P Schwellnus

A review of current literature and research was conducted into the cause of muscle cramping. The two most commonly used hypotheses are the dehydration and subsequent electrolyte depletion theory and the altered neuromuscular control theory.

After reviewing previous research, it became apparent that the dehydration and electrolyte depletion theory was generally not supported, although only small studies have been conducted. Secondly, this theory does not offer plausible pathophysiological mechanisms to explain the presentation and effective treatment of cramp.

Evidence for the altered neuromuscular control theory is centered around evidence from studies in human models of muscle cramping, epidemiological studies in cramping athletes, and animal experimental data.

The author concludes that whilst more research is needed to confirm the altered neuromuscular control theory, current research suggests that this best explains the mechanism and symptoms of muscle cramp.

British Journal of Sports Medicine 2009;43:401-408

According to a new study, a culprit for overuse running injuries which is often overlooked, is weakened hip muscles.“Various studies have estimated that up to 70% of runners suffer an overuse running injury every year” lead author Reed Ferber, Assistant Professor and Director of the Running Injury Clinic from the University of Calgary.

Literature review has revealed that excessive foot pronation and reduced hip muscle strength are the most common causes for overuse running injuries. “Hip muscle weakness especially appears to lead to atypical lower extremity mechanics and increases forces on knees and feet while running.”

The review quotes from studies which have found that after 4-6 weeks of hip abductor strength training, 22 out of 24 runners suffered less pain and between 35 and 51% demonstrated increased hip abductor strength.

“These results suggest that hip strengthening rehabilitation programmes may be an effective way to lessen running overuse injuries,” said Dr. Ferber.

He recommends performing hip abductor strengthening exercises to prevent injury. Individuals should progress up to three sets of 10 repetitions gradually to avoid muscle soreness.

This review was taken from the human kinetics blog

Sherman KJ, Cherkin DC, Hawkes RJ, Miglioretti DL, Deyo RA.

Massage has long been used in the treatment of chronic neck pain. This study has been undertaken in order to evaluate the effectiveness of therapeutic massage and wether it is more beneficial than a self-care book for patients.

64 patients with chronic neck pain were randomly placed in 2 groups to receive either up to 10 massages over 10 weeks or a self-care book. Follow-up telephone interviews after 4, 10, and 26 weeks assessed outcomes including dysfunction and symptoms.

After 10 weeks, more participants in the massage group experienced a significant improvement on the Neck Disability Index and on the symptom bothersomeness scale. After 26 weeks, those in the massage group reported improved function, but not symptom bothersomeness. The difference between the goups was significant at week 4 only.
This study suggests that massage is safe and may have clinical benefits for treating chronic neck pain at least in the short term. A larger trial is warranted to confirm these results.

Clin J Pain. 2009, 25(3), 233-8.

K. Donald Shelbourne, Tinker Gray and Marc Haro

The incidence of re-injury to either knee following an ACL reconstruction has not been thoroughly studied. The authors hypothesised that women would have a higher incidence of ACL injury in the contralateral knee following surgery that men would. However they did not think that there would be a difference in re-injury rate in the reconstructed knee.

Over a 5 year period, 1820 ACL recon patients were monitored for injuries. Any resulting injuries were recorded, including age, sex and activity level post surgery.

The entire 5 year period was completed in 1415 patients. Seventy-five of these patients had an injury to the contralateral knee, and 61 patients suffered an injury to the reconstructed knee. Women suffered more injuries (7.8%) to the contralateral normal knee than men (3.7%; P < .001) but not more injuries to the reconstructed knee. Out of the patients under the age of 18 17% suffered a subsequent injury, compared to 7% in the 18-25 age group and only 4% in over 25’s. Returning to sport prior to 6 months following surgery resulted in no increase in injury rate.

The study concluded that women are more likely to injure the acl in the contralateral knee following ACL surgery. Younger people are also more likely to suffer any knee injury on either side, as are those with a higher activity level. Returning to full activities before 6 months made no impact on injury occurrence.

American Journal of Sports Medicine, February 2009, 37:246-251

BECKETT, JAMES R. J.; SCHNEIKER, KNUT T.; WALLMAN, KAREN E.; DAWSON, BRIAN T.; GUELFI, KYM J.

This study examined the effects of static stretching in the recovery periods of field-based team sports on subsequent repeated sprint ability (RSA) and change of direction speed (CODS) performance.

on 4 days, 12 male team-sport players completed a standardised warm-up, followed by a test of either RSA or CODS. Both tests involved three sets of maximal sprint repetitions, with each set containing 6 reps. A 4-min recovery was permitted between sets. During this rest, the participants either rested (control) or completed a static stretching protocol. The RSA test involved straight-line sprints, whereas the CODS test required a change of direction (100°) every 4 m. Mean, total (sum of six sprints), first, and best sprint times were recorded for each set.

Results show there was a tendency for RSA times to be slower after the static stretching intervention. Further, sprint times again tended to be slower in the CODS trial for the stretching group, across all sprint variables, with a significantly slower ‘best sprint time’ in set 3 after static stretching.

These results suggest that static stretching of the legs between efforts may negatively affect RSA performance but has less effect on CODS performance.

Medicine & Science in Sports & Exercise:Volume 41(2)February 2009pp 444-450

Richard B. Souza, Christopher M. Powers

The aim of this study is to determine whether women with patellofemoral pain (PFP) show differences in hip kinematics, hip muscle strength, and hip muscle activation in comparison to pain-free controls.

21 females with PFP and 20 pain-free controls were used in this research. Hip kinematics and activity level of hip musculature were obtained during running, a drop jump, and a step-down maneuver. Isometric hip muscle torque production was quantified using a multimodal dynamometer.

Results showed that females with PFP had a greater peak hip internal rotation compared to the control group. The individuals in the PFP group also exhibited reduced hip torque production compared to the control group. Greater gluteus maximus recruitment was observed for individuals in the PFP group during running and the step-down task.

The study shoes that females in the PFP group had increased hip internal rotation and reduced hip muscle strength. They also activated Gluteus Maximus more than the control individuals, suggesting that they were attempting to recruit a weaker muscle in order to stabilise the hip. Our results support the proposed link between abnormal hip function and PFP.

J Orthop Sports Phys Ther 2009;39(1):12-19

Myer, Gregory D; Ford, Kevin R; Barber Foss, Kim D; Liu, Chunyan; Nick, Todd G; Hewett, Timothy E

The aim of this study was to examine the relationship between quadriceps and hamstrings strength in anterior cruciate ligament (ACL) injury risk in female athletes.

22 female athletes who subsequently suffered confirmed noncontact ACL ruptures were matched (1:4 ratio) to 88 female controls using limb, pubertal status, sport, and nearest height and mass. In addition, 22 male controls were used to serve as a secondary comparative control.

Those who subsequently suffered ACL injuries had decreased hamstring strength compared to the female and male controls. Conversely, the ACL injury groups subjects did not differ compared to the male controls in quadriceps strength, and the female controls demonstrated decreased quadriceps strength relative to the male controls.

This studies results show that female athletes who went on to suffer ACL injury had a combination of lower hamstring strength but equal quadriceps strength compared to males. Interestingly, female controls who did not suffer ACL injuries had lower quadriceps strength and equal hamstrings strength compared to matched male athletes.

Clinical Journal of Sport Medicine:Volume 19(1)January 2009pp 3-8

Rebecca Avrin Zifchock, Irene Davis

Although the use of custom orthotics and insoles can be extremely successful in treating certain lower limb injuries in individuals with either a high or low arch, the expense of such items can limit their use. Orthotic manufacturers have begun to offer a less expensive, semi-custom alternative such as heat moldable models. This study aimed to compare the rearfoot control and comfort in their semi-custom models, to their more costly, custom made counterparts.Altogether 37 participants took part, all being assessed for rearfoot kinematics and comfort in the custom orthotics, semi-custom orthotics and barefoot.

Compared to the barefoot condition, both orthotics were effective at reducing eversion velocity, although the custom device significantly decreased eversion velocity (P = 0.03), whereas the semi-custom device showed only a trend toward decreased eversion velocity (P = 0.09). Eversion excursion was significantly reduced with both orthotics (P < 0.01). Individuals with high arches were more comfortable in the semi custom orthotics, although the differences were small.

This research has shown that the semi-custom orthotics are a feasible alternative to the custom orthotics in terms of comfort and controlling rear foot motion.

Clinical Biomechanics, Volume 23, Issue 10, Pages 1209-1304 (December 2008)

Richard A. Ekstrom, Roy W. Osbourn, Patrick L. Hauer

The aim of this study was to analyze the longissimus thoracis and lumbar multifidi muscle activity during exercises used in back rehabilitation programs. EMG analysis of exercises was used to measure muscle activation to give a clearer idea of the effect the exercises have on these muscles for stabilisation, endurance, or strength training.

Bilateral surface EMG analysis of the longissimus thoracis and lumbar multifidi was carried out on 3 different groups whilst they performed a range of exercises commonly used in low back rehabilitation programs. In total there were 89 subjects. All EMG data during exercises was normalised to a percent of the maximum voluntary isometric contraction (MVIC).

Prone lumbar extension to end range against resistance produced the most activity in these two muscle groups (mean SD 92%± 12%). Prone lumbar extension to neutral, resisted lumbar extension while sitting, and prone extension with the upper and lower extremities lifted (Superman exercise) produced lower EMG amplitudes (77% ± 13% to 82% ± 12% MVIC). Bridging exercises, the side-bridge exercise, and upper and lower extremity raises (superman exercise) in either the prone or quadruped positions produced much lower activity (less than 50% MVIC).

These findings may be helpful in assisting physical therapists in selecting exercises to progress a patient from low-intensity to those that require more muscle activity.

J Orthop Sports Phys Ther. 2008;38(12):736-745.