Overview
Prepatellar bursitis, or inflammation of the prepatellar bursa located over the kneecap, commonly results from repetitive trauma or prolonged pressure on the knee, often seen in individuals who kneel frequently such as plumbers, carpet layers, and gardeners. This condition can also arise post-surgical interventions around the knee, including arthroscopic procedures and total knee arthroplasty (TKA). Clinically significant due to its potential to cause significant pain and functional impairment, prepatellar bursitis affects individuals across various age groups but is more prevalent in occupational settings where kneeling is frequent. Accurate diagnosis and timely management are crucial in day-to-day practice to prevent chronic issues and ensure optimal patient function 13.Pathophysiology
Prepatellar bursitis typically develops when the bursa, a small fluid-filled sac that reduces friction between moving structures, becomes irritated or inflamed due to repetitive mechanical stress or direct trauma. The repetitive pressure or friction leads to an inflammatory response characterized by increased vascular permeability and the accumulation of synovial fluid within the bursa. This accumulation causes swelling and tenderness over the prepatellar region. In some cases, particularly following surgical interventions like knee arthroscopy or TKA, infection can complicate this process, leading to more severe symptoms and potential systemic involvement if not promptly addressed. The inflammatory cascade involves cytokines and chemokines that attract inflammatory cells, further exacerbating the swelling and pain 13.Epidemiology
While specific incidence and prevalence figures for prepatellar bursitis are not extensively detailed in the provided sources, the condition is recognized as a common occupational hazard among individuals engaged in activities requiring frequent kneeling. Age and sex distributions are not explicitly delineated in the given literature, but it is generally observed across all age groups with a notable prevalence among middle-aged and older adults due to cumulative occupational stress. Geographic distribution is not specifically addressed, but occupational risk factors can vary by region and industry standards. Trends over time suggest an increasing awareness and reporting due to improved diagnostic techniques and occupational health initiatives 13.Clinical Presentation
The typical presentation of prepatellar bursitis includes localized swelling, tenderness, and pain over the prepatellar region, often exacerbated by kneeling or pressure on the knee. Patients may report a gradual onset of symptoms following prolonged kneeling or recent trauma. Atypical presentations might include systemic symptoms if infection is present, such as fever, malaise, and increased pain and swelling. Red-flag features include significant warmth, erythema, and systemic signs of infection, which necessitate urgent evaluation for potential septic bursitis. Prompt recognition of these features is crucial for timely intervention 13.Diagnosis
The diagnostic approach for prepatellar bursitis involves a thorough clinical history and physical examination, focusing on the nature and duration of symptoms, occupational history, and any recent trauma. Key diagnostic criteria include:Differential Diagnosis:
Management
Initial Management
Second-Line Management
Refractory Cases / Specialist Referral
Complications
Common complications include chronic bursitis if left untreated, leading to persistent swelling and pain. Infection poses a significant risk, potentially progressing to septic arthritis or systemic infection if not promptly addressed. Referral to orthopedic surgery is warranted for recurrent or refractory cases, especially those involving structural damage or persistent infection 13.Prognosis & Follow-up
The prognosis for prepatellar bursitis is generally good with appropriate management, often leading to complete resolution within weeks to months. Prognostic indicators include early diagnosis, absence of infection, and adherence to conservative treatment protocols. Recommended follow-up intervals include clinical reassessment at 2-4 weeks post-initial treatment, with imaging or repeat aspiration if symptoms persist. Long-term monitoring may be necessary in recurrent cases to prevent chronic complications 13.Special Populations
Occupational Risk Groups
Individuals engaged in occupations requiring frequent kneeling, such as construction workers and gardeners, are at higher risk and may require more vigilant monitoring and preventive measures.Post-Surgical Patients
Patients who have undergone knee surgeries, including arthroscopy and TKA, are at increased risk for bursitis due to altered biomechanics and potential wound complications. Close follow-up and early intervention are crucial in this population 13.Key Recommendations
References
1 Gu A, Fassihi SC, Wessel LE, Kahlenberg C, Ast MP, Sculco PK et al.. Comparison of Revision Risk Based on Timing of Knee Arthroscopy Prior to Total Knee Arthroplasty. The Journal of bone and joint surgery. American volume 2021. link 2 Domzalski M, Karauda A, Grzegorzewski A, Lebiedzinski R, Zabierek S, Synder M. Anterior Cruciate Ligament Reconstruction Using the Transphyseal Technique in Prepubescent Athletes: Midterm, Prospective Evaluation of Results. Arthroscopy : the journal of arthroscopic & related surgery : official publication of the Arthroscopy Association of North America and the International Arthroscopy Association 2016. link 3 Liu HW, Gu WD, Xu NW, Sun JY. Surgical approaches in total knee arthroplasty: a meta-analysis comparing the midvastus and subvastus to the medial peripatellar approach. The Journal of arthroplasty 2014. link 4 Engh GA, Parks NL. Surgical technique of the midvastus arthrotomy. Clinical orthopaedics and related research 1998. link