Use of the Patellar-Pubic Percussion Test in the Diagnosis and Management of a Patient with a Non-Displaced Hip Fracture

This case report describes the diagnosis and subsequent medical and physical therapy management of a 68-year-old patient with an undiagnosed non-displaced hip fracture. Initial plain film radiographs and a computed tomography (CT) scan of the involved hip were both interpreted as negative. One of the findings on the physical examination included a positive patellar-pubic percussion test (PPPT). This finding in a female patient of this age raised the suspicion of an occult hip fracture and she was referred back to her primary care physician. Repeat radiographs revealed a non-displaced hip fracture and the patient was treated surgically. The PPPT is an easy-to-implement clinical examination tool that may be extremely useful in physical therapy practice to guide the decision-making process for patients with suspected hip fractures. The utilization of the PPPT by the treating physical therapist for the patient in this case report contributed to a timely diagnosis, potentially preventing the disabling sequelae associated with a displaced femoral fracture.Key Words: Differential Diagnosis, Physical Therapy, Femoral Neck Fracture, Patellar-Pubic Percussion TestThe Guide to Physical Therapist Practice¹ described referral to another health care practitioner as one possible outcome of the physical therapist''s examination. The literature has provided several such examples where patient referral by the physical therapist to a physician led to a more timely diagnosis of a variety of serious diseases and disorders. A number of these cases involved patients with hip pain who were subsequently diagnosed with a hip fracture^2–5. For example, Gurney, Boissonnault, and Andrews³ described a patient referred to physical therapy for right hip pain with probable osteoarthritis. Radiographs taken prior to the initial physical therapy visit revealed mild degenerative joint disease with some osteophytosis and a normal femoral neck/shaft angle. Patient presentation and examination led the therapist to suspect a diagnosis other than osteoarthritis. Subsequent magnetic resonance imaging (MRI) revealed a femoral neck and head stress fracture that was confirmed by bone scan.Hip fractures can be difficult to diagnose and misdiagnosing an occult hip fracture is not unique to patients referred to physical therapy. Perron et al⁶ described a case of a 79-year-old female who presented at the emergency department after a fall onto her left side. Plain films were obtained and interpreted as negative. Three days after her fall she returned to her primary care physician complaining that her symptoms were worse. Again, plain films did not show any fracture; however, a bone scan showed significant uptake suggestive of a hip fracture. A subsequent MRI confirmed a femoral neck fracture. File et al⁷ discussed an 85-year-old woman with a traumatic right hip injury 12 hours prior to evaluation. Examination was negative for physical deformities or discrepancies, as were initial radiographs. At five days post-accident, she returned to the emergency department with progressively worse hip pain. Follow-up radiographs revealed a Garden type III fracture of her right femoral neck.In the United States, hip fractures have a yearly incidence of about 300,000^6,8. With the aging of the population, this incidence is expected to double or even triple by the year 2040⁶. Morbidity and mortality after a hip fracture are reported to be as high as 14–36% in the first year after injury^6,8. Table ​Table11 provides signs and symptoms associated with femoral neck/head fractures^2,4,5,9–12. Most patients with hip fractures present with observable deformity and are definitively diagnosed with plain film radiographs^6–8. However, in 2–10% of the patients presenting with a painful hip after trauma, initial radiographs may not show the occult fracture¹³. An occult fracture is defined as one that is suspected clinically but that is not seen on radiographic examination¹⁴. These patients may have a history of a relatively minor trauma, absence of observable deformities, and relatively normal range of motion⁷. Generally they will be able to ambulate; however, they will most likely have an antalgic gait pattern. Patients with an occult, non-displaced hip fracture are at risk for a displaced fracture that often leads to avascular necrosis and the need for surgical intervention. Once these complications arise, return to full pre-injury activity level is often not attainable. Timely diagnosis might minimize morbidity and mortality and prevent the progressive loss of function typically associated with a hip fracture^6,8,13.

TABLE 1

Signs and symptoms associated with hip fracture^{2,4,5,9,10,14,18}.

Presenting patient signs and symptoms

• Groin pain

• Hip pain

• Thigh pain

• Buttock pain

• Abnormal hip range of motion

• Tenderness around the hip

• Antalgic gait

Absent or untested signs and symptoms

• Abnormal spine ROM

• Pain with straight leg raise

• Coxa vara (diagnosed by radiograph)

• Total hip or knee arthroplasty

• Night pain

• Positive patellar-pubic percussion test

Open in a separate windowFile et al⁷ reported a positive patellar-pubic percussion test (PPPT) as an additional clinical examination sign helpful for the diagnosis of occult hip fractures. The purpose of this case report is to describe a patient with hip pain receiving care from a physical therapist and the influence that a positive finding on the PPPT had on the therapist''s decision-making, culminating in the diagnosis of a non-displaced femoral fracture.