Bursitis is characterized by an inflammation of a bursa—a synovium fluid-filled pouch-shaped structure usually found close to large joints, such as the knee, hip, elbow, and shoulder. The main function of bursae is the reduction of resistance between moving structures, such as the bone, tendon, and skin [1]. The main causes of bursitis are the excessive use of the joint, trauma, repeated microtraumas, crystal deposits, infection, hemorrhage, and systemic inflammation [2].

The type of bursitis that is affecting the knee joint can be divided into four categories: suprapatellar, prepatellar, deep infrapatellar, and superficial infrapatellar [3]. The deep infrapatellar bursa is located between the anterior tibial tuberosity and the posterior of the distal patellar tendon, inferior to the infrapatellar fat pad [4,5]. Owing to its relatively deep location, infrapatellar bursitis is difficult to diagnose by clinical examination alone. Bursitis can be diagnosed via magnetic resonance imaging (MRI) and can be detected early via musculoskeletal ultrasonography [5].

Patients with bursitis are typically treated conservatively using methods, such as cold therapy, activity modification, and nonsteroidal anti-inflammatory drugs [6]. If necessary, lidocaine and corticosteroids can be injected to treat inflammatory areas directly, and surgical treatments, such as debridement or excision, might be required if infection is suspected or not alleviated by conservative treatment [7,8]. To date, only a few studies have reported the effectiveness of Korean medicine treatments for infrapatellar bursitis. Thus, this study aims to report a patient with right anterior knee pain who was diagnosed with deep infrapatellar bursitis and treated with integrated Korean medicine.

This report and the associated retrospective review of the patient’s medical records were approved by Jaseng Hospital of Korean Medicine of Institutional Review Board (no. 2023-07-030).

1. Medical history

This study included a 27-year-old male who had pain at the front of his right knee, which was accompanied by mild bruising, redness, and swelling beginning in April 2022. The pain intensified when standing and walking as the patient was supporting his weight with his knees. Knee joint flexion and extension were possible, but when bending the right knee at 90 degrees, the patient experienced pain at the front of the knee. Local clinics had prescribed nonsteroidal anti-inflammatory drugs, but the patient continued to experience severe pain. He first visited Jaseng Hospital of Korean Medicine on May 3, 2022, and was admitted on the same day.

2. Radiography and MRI

On May 3, the radiographic findings of both knees of the patient revealed no remarkable findings (Fig. 1). However, The MRI results on May 5 indicated deep infrapatellar bursitis, soft-tissue edema in the subcutaneous fat around the knee, prefemoral fat pad impingement syndrome, and iliotibial band friction syndrome (Fig. 2), resulting in a diagnosis of knee bursitis.

Figure 1. A bilateral knee radiograph (May 3, 2022) revealed no remarkable findings.

Figure 2. The MRI of the right knee (May 5, 2022) revealed deep infrapatellar bursitis on (a) a sagittal image (arrow) and (b) axial image (arrow).

3. Treatment

Sterilized, disposable stainless steel needles with a size of 0.25 × 40 mm were inserted into the distal patellar tendon of the right knee. Moreover, electroacupuncture was performed twice daily at an intensity of 2 Hz for 15 minutes using needles that penetrate the EX-LE4 and EX-LE5 on the right knee. The patient also had Shinbaro 2 pharmacopuncture twice daily (4 mL daily) through a 1 mL/cc insulin syringe attached to a disposable 29- gauge 13 mm needle. The needle was inserted at a depth of 1 cm, while 1 mL of the Shinbaro 2 compound was injected into the left and right sides of the distal patellar tendon, respectively (Table 1). The total treatment period was 15 days during hospitalization.

Table 1 . Pharmacopuncture details.

Prescription	Components	Proportions (g/mL)	Administration
SJ3-SBO Shinbaro 2	Paeonia lactiflora Ostericum koreanum Kitagawa Aralia continentalis Eucommiae Cortex Radix Achyranthis Rhizoma Cibotii Radix Ledebouriellae Cortex Acanthopanacis Scolopendra subspinipes mutilans	0.0027 0.0013 0.0013 0.0013 0.0013 0.0013 0.0013 0.0013 0.0013	Days 1–15: 2 vials daily (2 mL/vial)

The patient was prescribed with Dangguisusan, a herbal medicine that exhibits anti-inflammatory effects and improves subcutaneous hematoma, 3 times daily for 15 days [9]. Table 2 shows the herbal components of Dangguisusan.

Table 2 . Dangguisusan herbal medicine details.

Prescription	Components	Proportions (g/pouch)	Administration
Dangguisusan	Radix Angelicae Gigantis Radix Paeoniae Rubra Radix Linderae Rhizoma Cyperi Lignum Sappan Flos Carthami Semen Persicae Cinnamomi Cortex Glycyrrhizae Radix et Rhizoma	1.500 1.000 1.000 1.000 1.000 0.800 0.700 0.600 0.500	Days 1–15: 3 pouches daily orally

4. Assessments

The patient’s subjective score of overall pain was measured using a patient-reported numerical rating scale (NRS) ranging from 0 to 10 (minimal pain to worst pain). The knee joint function was evaluated using the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) Index on a scale ranging from 0 points for minimal pain to 96 points for worst pain. The patient’s quality of life was measured using the EuroQoL-5D questionnaire (EuroQoL Research Foundation, Rotterdam, Netherlands), which was scored in five dimensions, with the best score being 1 point and the worst score being 0 points.

The patient’s knee joint movement (range of motion, ROM) was measured for flexion, extension, and lateral bending. Specialty tests, such as the valgus and varus stress tests, were also performed to evaluate other knee conditions.

5. Response to treatment

On the day of admission, the patient had anterior pain in the right knee, with an NRS score of 6, WOMAC score of 63, and a ROM assessed as flexion of 90/135 and extension of 0/0. After eight days of hospitalization, the overall right knee pain began to decrease, with an NRS score of 4 and WOMAC score of 44.

On the day of discharge (May 17 2022), the patient had an NRS score of 3 and WOMAC score of 30 on the right knee. With regard to the WOMAC questionnaire results, his pain score decreased from 13 to 7, physical function score decreased from 47 to 20, and stiffness score remained at 3 as evaluated upon admission. He also reported that the overall pain in the right knee was significantly reduced when climbing stairs and walking, with elimination of nyctalgia and recovery of function (Figs. 3, 4). The EuroQOL-5D questionnaire score, which had been 0.344 on the day of admission and 0.659 on Day 8 of hospitalization, was 0.719 on the day of discharge (Fig. 5). His ROM had also recovered to a flexion of 135/135 and extension of 0/0 at discharge, with all specialty tests being normal at both admission and discharge (Table 3). No side effects from his treatments were observed during his hospitalization.

Table 3 . Results of the range of motion and specialty tests.

Test date (2022)	Range of motion												Specialty tests
	Flexion			Extension			Lateral bending						Stress varus		Stress valgus
	Right	Left		Right	Left		Right			Left
							Right	Left		Right	Left
May 3	90	135		0	0		5	5		5	5		-	-	-	-
May 10	110	135		0	0		5	5		5	5		-	-	-	-
May 17	135	135		0	0		5	5		5	5		-	-	-	-

Figure 3. Change in the patient-reported numeric rating scale for right knee pain during the patient’s hospitalization.

Figure 4. Changes in the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) index during the patient’s hospitalization.

Figure 5. Changes in the EuroQoL-5D (EuroQoL Research Foundation, Rotterdam, Netherlands) scores during the patient’s hospitalization.

Although many case reports on infrapatellar bursitis have been conducted, to date, no study has assessed the effect of integrated Korean medicine on this condition. Thus, this study aimed to report a patient with infrapatellar bursitis who received Korean medicine treatments consisting of acupuncture, pharmacopuncture, and herbal medicine. Over 15 days of hospitalization, the patient achieved pain relief and improved physical function.

Acupuncture is the most commonly used method to control both acute and chronic pain. Acupuncture mediates analgesia through opioid peptides and their receptors in the arcuate nucleus-periaqueductal gray-nucleus raphe magnus-spinal dorsal horn pathway, while electroacupuncture mediates analgesia by producing opioid peptides called enkephalin or dynorphin in the spinal cord depending on the value of the Hertz applied [10]. In pharmacopuncture, herbal medicine is injected into the acupuncture points, thus coupling the physical stimulation of conventional acupuncture with the pharmacologic effects of herbal medicine. Because the herbal extracts are absorbed directly into the treatment area without the need to pass through the gastrointestinal tract, the effect of pharmacopuncture can be observed immediately after treatment, especially in musculoskeletal diseases [11]. Shinbaro pharmacopuncture uses a purified compound extracted from a mixture of six herbal medicines (i.e., Radix Ledebouriellae, Radix Achyranthis, Acanthopanacis Cortex, Rhizoma Cibotii, Semen Glycine, Eucommiae Cortex) that have traditionally been used to treat inflammatory and bone diseases. The compound has anti-inflammatory and antinociceptive effects and protects and recovers joint cartilage [12]. When injected into the area of infrapatellar bursitis, it can potentially suppress inflammation, relieve pain, and improve overall function.

Dangguisusan, a compound found in nine herbal medicines (Radix Angelicae Gigantis, Radix Paeoniae Rubra, Radix Linderae, Rhizoma Cyperi, Lignum Sappan, Flos Carthami, Semen Persicae, Cinnamomi Cortex, Glycyrrhizae Radix et Rhizoma), has been proven to inhibit the activity of inflammatory mediators, such as nitric oxide, interleukins 1β and 6, and tumor necrosis factor-α; impede the inflammatory factor nuclear factor-κB; and activate the anti-inflammatory factor Nrf2 [9]. It has been difficult to find any reports of clinical effects on the treatment used by Shinbaro pharmacopuncture and Dangguisusan. However, there have been report [13] on the effect of Dangguisusan and Neutral Eohyeol (Yuxue) pharmacopuncture for fracture healing in the early stage, and report [14] on the effect of Dangguisusan and Homnis Placenta pharmacopuncture for lateral malleolus avulsion fracture. It has been confirmed that Dangguisusan is usually used for traffic accident patients with acute cervicolumbar sprain and fracture patients through the improvement of subcutaneous hematoma and anti-inflammatory effects [15]. It also has been confirmed that the Shinbaro pharmacopuncture is used for cervicolumbar spinal herniated Intervertebral disc patients and traffic accident patients through the effect of anti-inflammatory [16,17]. More research is needed in the future to secure evidence of anti-inflammatory effects of treatments combined with Shinbaro pharmacopuncture and Dangguisusan.

This study has several limitations. First, considering that this study included only one patient, the level of evidence was not high. Second, since no control group was available as a comparator, definitively attributing the patient’s results to the given treatments is difficult. Third, additional post-treatment evaluations using follow-up MRI are needed. Nevertheless, an advantage of this case study is that it is the first to report the effectiveness of Korean medicine treatments for anterior knee pain caused by infrapatellar bursitis. Although integrated Korean medicine could potentially be an alternative conservative treatment in infrapatellar bursitis, a randomized controlled trial is needed to determine the regimen’s effectiveness and long-term results.

In conclusion, this case report describes the efficacy of integrated Korean medicine treatments in the case of infrapatellar bursitis. During hospitalization, it was observed that the patient regained physical function, including climbing stairs and walking, and experienced an improvement in overall pain. Furthermore, integrated Korean medicine treatments can be considered an effective therapeutic option for patients diagnosed with infrapatellar bursitis.

Conceptualization: MYY, JJH. Data curation: JSK, GBL. Formal analysis: MYY, JSK. Investigation: MYY, DJY. Methodology: JJH, GBL. Project administration: HWC, DJK. Resources: DJY, DYK. Software: MYY, DYK. Supervision: HWC, DJK. Validation: MYY. Visualization: MYY. Writing – original draft: MYY. Writing – review & editing: All authors.

The authors have no conflicts of interest to declare.

None.

This research did not involve any human or animal experiments.