Review for the generalist: evaluation of anterior knee pain

Patella-patellar tendon angle and lateral patella-tilt angle decrease patients with chondromalacia patella

PURPOSE

The aim of the present study was to evaluate the effect of patellofemoral joint morphology and patellar alignment (lateral patellar tilt and sagittal patellar tilt) on the presence and stage of CP, and identify the differences between sexes.

METHODS

MRI of 243 patients [146 men (60.1%)] were evaluated retrospectively. Patients were grouped as normal group without chondromalacia, group with mild chondromalacia (grades 1-2) and group with severe chondromalacia (grades 3-4). Sagittal patellofemoral alignment was assessed by the angle between the patella and patellar tendon (P-PTA), and the angle between the quadriceps tendon and patella (Q-PA). Patellar tilt was assessed by lateral patellar tilt angle (LPTA). In addition, patellofemoral joint morphology was evaluated by measuring trochlear depth (TD), trochlear sulcus angle (TSA) and patella angle (PA).

RESULTS

P-PTA, Q-PA, LPTA and TD values were significantly lower in patients with severe chondromalacia than in patients with both normal and mild chondromalacia (P < 0.001). TSA values were significantly higher in patients with severe chondromalacia than those with both normal and mild chondromalacia (P < 0.001). TSA was higher and TD was lower in women compared to men (P < 0.001). LPTA and P-PTA were lower in women compared to men, and the difference was significant. There was no difference in PA between the two sexes.

CONCLUSIONS

Patellar cartilage degeneration increases with trochlear dysplasia. There is a strong correlation between patellar malalignment (lateral patellar tilt and sagittal patellar tilt) and chondromalacia patella. Women are more prone to developing CP than men.

Investigation of the Relationship between Anterior Knee Pain and Chondromalacia Patellae and Patellofemoral Malalignment

Objective

The study aimed to investigate whether there is any association of anterior knee pain and knee function with chondromalacia stage and patellofemoral alignment in patients with anterior knee pain for over a month and with chondromalacia patellae (CMP) detected by magnetic resonance imaging (MRI).

Materials and Methods

We reviewed the medical records of 38 patients who underwent a knee MRI examination and were diagnosed with chondromalacia based on the MRI. Knee MRI images were evaluated by a radiologist for chondromalacia staging. Patients were divided into two groups as early stage (stage 1-2) and advanced stage (stage 3-4) chondromalacia. Patients' demographical data (age, sex, and occupation), clinical features, physical examination findings and patellofemoral pain severity scale, kujala patellofemoral scoring system, and functional index questionnaire scores were obtained from their medical records. Trochlear sulcus angle, sulcus depth, lateral patellofemoral angle, patellar translation, and Insall-Salvati index were measured using the MRI images.

Results

The mean patient age was higher in the advanced stage CMP group compared to the early stage CMP group (p=0.038). There was no statistically significant difference regarding other demographical data (p>0.05). MRI measurement parameters did not show difference between the groups (p>0.05). Patients in the advanced stage CMP group had higher patellofemoral pain severity score, lower kujala patellofemoral score, and lower functional index questionnaire score compared to the early stage CMP group. The differences were statistically significant (p=0.008, p=0.012, and p=0.026, respectively).

Conclusion

As chondromalacia stage advances, the symptom severity worsens and knee functions decline; however, MRI measurements do not show difference between early and advanced stage CMP patients.

The child with joint pain in primary care

Joint pains are a common reason for children to present to primary care. The differential diagnosis is large including some diseases that do not primarily affect the musculoskeletal system. Although the cause for many patients will be benign and self-resolving, in rare cases the diagnosis is associated with long-term morbidity and mortality if not detected early and appropriately treated. These include primary and secondary malignancies, septic arthritis, osteomyelitis, inflammatory arthritis, slipped upper femoral epiphysis (SUFE) and non-accidental injury. We highlight the importance of a thorough history and directed yet comprehensive examination. A diagnostic algorithm is provided to direct primary care physicians' clinical assessment and investigation with the evidence base where available. In many cases, tests are not required, but if there is suspicion of malignancy, infection or inflammatory conditions, laboratory tests including full blood count, blood film, erythrocyte sedimentation rate, C-reactive protein and lactate dehydrogenase help to support or exclude the diagnosis. Autoimmune tests, such as antinuclear antibodies and rheumatoid factor, have no diagnostic role in juvenile idiopathic arthritis; therefore, we advise against any form of 'rheumatological/autoimmune disease screen' in primary care. Imaging does have a place in the diagnosis of joint pains in children, with plain radiographs being most appropriate for suspected fractures and SUFE, whilst ultrasound is better for the detection of inflammatory or infective effusions. The appropriate referral of children to paediatric rheumatologists, oncologists, orthopaedic surgeons and the emergency department are discussed.

MRI findings of young male soldiers with atraumatic anterior knee pain

The purpose of this study is to investigate abnormal magnetic resonance image (MRI) findings of young active males with atraumatic anterior knee pain (AKP). Targeting young male soldiers, we prospectively gathered and analyzed 157 knee MRIs from patients with atraumatic AKP (AKP group) and 53 knee MRIs from patients without knee pain (control group). Abnormalities of the patellofemoral (PF) joint and extensor mechanism on MRI were more common in the AKP group than the control group (48% vs 13%, P < 0.001). The overall prevalence of medial plica (34% vs 13%, P = 0.004) and the prevalence of the thick medial plica (9% vs 0%, P = 0.023) were considerably higher in the AKP group. The cartilaginous sulcus angle in the AKP group without abnormalities on MRI was significantly higher than both the AKP group with abnormalities and the control group (145° vs 141° vs 142°, respectively, P = 0.001). Our results suggest that careful assessment of young, active males with atraumatic AKP is warranted regarding PF joint abnormalities, particularly the presence of medial plica and/or subtle abnormalities of the articular geometry. The results from the present study could be used for the management of patients with AKP.

Short-term effects of patellar kinesio taping on pain and hop function in patients with patellofemoral pain syndrome

Background:

Patellofemoral pain syndrome (PFPS) is the most prevalent orthopaedic condition among physically active individuals, contributing to an estimated 30% to 40% of all sports medicine visits. Techniques using Kinesio Tape (KT) have become increasingly popular; however, there has been scant research supporting its use on patients with PFPS.

Hypothesis:

The use of patellar KT to treat patients with PFPS will provide a statistically significant improvement in short-term pain and single-leg hop measures as compared with sham placement of KT.

Study Design:

Nonrandomized controlled clinical trial with repeated-measures design.

Level of Evidence:

Level 3.

Methods:

Forty-nine subjects (41 females, 8 males) between the ages of 12 and 24 years with PFPS participated in this study. Each subject underwent patellar kinesio taping with both experimental and sham applications while completing 4 functional tasks and the single-leg triple jump test (STJT). The treatment outcome was analyzed using separate paired t tests to measure improvement on a numeric pain rating scale. A 2-way, 2 × 2 analysis of variance was used to analyze the relationship between taping condition (experimental vs sham) and side (involved vs uninvolved) for STJT scores.

Results:

Separate paired t tests found step-up, step-down, and STJT pain improvement statistically significant between taping conditions. The 2-factor analysis of variance yielded a significant main effect for taping condition, but the main effect for side was not significant. The interaction between taping condition and side was significant. This showed there was little change in STJT distance between repeated measures performed on the untaped, noninvolved leg. However, subjects’ STJT distances were significantly greater for the experimental KT application than the sham application for the involved side.

Conclusion:

Patellar kinesio taping provided an immediate and statistically significant improvement in pain and single-leg hop function in patients with PFPS when compared with a sham application. However, improvement in STJT scores did not surpass the minimally detectable change value, and therefore, the clinical effectiveness of KT for improving single-leg hop function was not established in the current study.

Clinical Relevance:

Kinesio Tape provides a viable, short-term method to control pain.

Diagnostic accuracy and association to disability of clinical test findings associated with patellofemoral pain syndrome

PURPOSE

To investigate the diagnostic accuracy and association to disability of selected functional findings or physical examination tests for patellofemoral pain syndrome (PFPS) in patients with anterior knee pain.

METHODS

A sample of 76 consecutive patients with anterior knee pain was further subdivided into PFPS and other diagnoses. Routine physical examination tests were examined in a prospective, consecutive-subjects design for a cohort of patients with anterior knee pain. Diagnostic accuracy findings, including sensitivity, specificity, positive (PPV) and negative (NPV) predictive value, and positive (LR+) and negative (LR-) likelihood ratios, were calculated for each test. PPV and NPV reflect the percentage of time of positive or a negative test (respectively) accurately captures the diagnosis of the condition. LR+ and LR- reflect alterations in post-test probability when the test is positive or negative (respectively). Lastly, associations to disability (International Knee Documentation Committee (IKDC) subjective form) were calculated for each clinical finding.

RESULTS

Diagnostic accuracy analyses of individual functional assessment and situational phenomena suggest that the strongest diagnostic test is pain encountered during resisted muscle contraction of the knee (PPV=82%; LR+=2.2; 95% CI: 0.99-5.2). Clusters of test findings were substantially more diagnostic, with any two of three positive findings of muscle contraction, pain during squatting, and pain during palpation yielding the following values: PPV=89%; LR+=4.0 (95% CI: 1.8-10.3). No individual or clustered test findings were significantly associated with the IKDC score.

CONCLUSION

Combinations of functional assessment tests and situational phenomena are diagnostic for PFPS and may serve to rule in and rule out the presence of PFPS. Single findings are not related to disability scores (IKDC).